diff --git a/src/main/java/com/libraryman_api/controller/BookController.java b/src/main/java/com/libraryman_api/controller/BookController.java
index 92601fe..7dea8dd 100644
--- a/src/main/java/com/libraryman_api/controller/BookController.java
+++ b/src/main/java/com/libraryman_api/controller/BookController.java
@@ -9,17 +9,36 @@
 
 import java.util.List;
 
+/**
+ * REST controller for managing books in the LibraryMan application.
+ * This controller provides endpoints for performing CRUD operations on books,
+ * including retrieving all books, getting a book by its ID, adding a new book,
+ * updating an existing book, and deleting a book.
+ */
 @RestController
 @RequestMapping("/api/books")
 public class BookController {
+
     @Autowired
     private BookService bookService;
 
+    /**
+     * Retrieves a list of all books in the library.
+     *
+     * @return a list of {@link Books} objects representing all the books in the library.
+     */
     @GetMapping
     public List<Books> getAllBooks() {
         return bookService.getAllBooks();
     }
 
+    /**
+     * Retrieves a book by its ID.
+     *
+     * @param id the ID of the book to retrieve.
+     * @return a {@link ResponseEntity} containing the {@link Books} object, if found.
+     * @throws ResourceNotFoundException if the book with the specified ID is not found.
+     */
     @GetMapping("/{id}")
     public ResponseEntity<Books> getBookById(@PathVariable int id) {
         return bookService.getBookById(id)
@@ -27,19 +46,36 @@ public ResponseEntity<Books> getBookById(@PathVariable int id) {
                 .orElseThrow(() -> new ResourceNotFoundException("Book not found"));
     }
 
+    /**
+     * Adds a new book to the library.
+     *
+     * @param book the {@link Books} object representing the new book to add.
+     * @return the added {@link Books} object.
+     */
     @PostMapping
     public Books addBook(@RequestBody Books book) {
         return bookService.addBook(book);
     }
 
+    /**
+     * Updates an existing book in the library.
+     *
+     * @param id          the ID of the book to update.
+     * @param bookDetails the {@link Books} object containing the updated book details.
+     * @return the updated {@link Books} object.
+     */
     @PutMapping("/{id}")
     public Books updateBook(@PathVariable int id, @RequestBody Books bookDetails) {
         return bookService.updateBook(id, bookDetails);
     }
 
+    /**
+     * Deletes a book from the library by its ID.
+     *
+     * @param id the ID of the book to delete.
+     */
     @DeleteMapping("/{id}")
     public void deleteBook(@PathVariable int id) {
         bookService.deleteBook(id);
     }
 }
-
diff --git a/src/main/java/com/libraryman_api/controller/BorrowingController.java b/src/main/java/com/libraryman_api/controller/BorrowingController.java
index 50fdc2b..a0597d9 100644
--- a/src/main/java/com/libraryman_api/controller/BorrowingController.java
+++ b/src/main/java/com/libraryman_api/controller/BorrowingController.java
@@ -4,46 +4,93 @@
 import com.libraryman_api.exception.ResourceNotFoundException;
 import com.libraryman_api.service.BorrowingService;
 import org.springframework.web.bind.annotation.*;
+
 import java.util.List;
 
+/**
+ * REST controller for managing borrowings in the LibraryMan application.
+ * This controller provides endpoints for performing operations related to borrowing and returning books,
+ * paying fines, and retrieving borrowing records.
+ */
 @RestController
 @RequestMapping("/api/borrowings")
 public class BorrowingController {
 
     private final BorrowingService borrowingService;
+
+    /**
+     * Constructs a new {@code BorrowingController} with the specified {@link BorrowingService}.
+     *
+     * @param borrowingService the service used to handle borrowing-related operations.
+     */
     public BorrowingController(BorrowingService borrowingService) {
         this.borrowingService = borrowingService;
     }
 
+    /**
+     * Retrieves a list of all borrowing records in the library.
+     *
+     * @return a list of {@link Borrowings} objects representing all borrowings.
+     */
     @GetMapping
     public List<Borrowings> getAllBorrowings() {
         return borrowingService.getAllBorrowings();
     }
 
+    /**
+     * Records a new book borrowing.
+     *
+     * @param borrowing the {@link Borrowings} object containing borrowing details.
+     * @return the saved {@link Borrowings} object representing the borrowing record.
+     */
     @PostMapping
     public Borrowings borrowBook(@RequestBody Borrowings borrowing) {
         return borrowingService.borrowBook(borrowing);
     }
 
+    /**
+     * Marks a borrowed book as returned.
+     *
+     * @param id the ID of the borrowing record to update.
+     */
     @PutMapping("/{id}/return")
     public void returnBook(@PathVariable int id) {
         borrowingService.returnBook(id);
     }
 
+    /**
+     * Pays the fine for an overdue book.
+     *
+     * @param id the ID of the borrowing record for which the fine is being paid.
+     * @return a message indicating the payment status.
+     */
     @PutMapping("/{id}/pay")
     public String payFine(@PathVariable int id) {
         System.out.println("Pay Fine Id: " + id);
         return borrowingService.payFine(id);
     }
 
+    /**
+     * Retrieves all borrowing records for a specific member.
+     *
+     * @param memberId the ID of the member whose borrowing records are to be retrieved.
+     * @return a list of {@link Borrowings} objects representing the member's borrowings.
+     */
     @GetMapping("member/{memberId}")
     public List<Borrowings> getAllBorrowingsOfAMember(@PathVariable int memberId) {
         return borrowingService.getAllBorrowingsOfMember(memberId);
     }
 
-
+    /**
+     * Retrieves a borrowing record by its ID.
+     *
+     * @param borrowingId the ID of the borrowing record to retrieve.
+     * @return the {@link Borrowings} object representing the borrowing record.
+     * @throws ResourceNotFoundException if the borrowing record with the specified ID is not found.
+     */
     @GetMapping("{borrowingId}")
     public Borrowings getBorrowingById(@PathVariable int borrowingId) {
-        return borrowingService.getBorrowingById(borrowingId).orElseThrow(() -> new ResourceNotFoundException("Borrowing not found"));
+        return borrowingService.getBorrowingById(borrowingId)
+                .orElseThrow(() -> new ResourceNotFoundException("Borrowing not found"));
     }
 }
diff --git a/src/main/java/com/libraryman_api/controller/GlobalExceptionHandler.java b/src/main/java/com/libraryman_api/controller/GlobalExceptionHandler.java
index 6581e1a..ece2876 100644
--- a/src/main/java/com/libraryman_api/controller/GlobalExceptionHandler.java
+++ b/src/main/java/com/libraryman_api/controller/GlobalExceptionHandler.java
@@ -10,8 +10,24 @@
 
 import java.util.Date;
 
+/**
+ * Global exception handler for the LibraryMan API.
+ * This class provides centralized exception handling across all controllers in the application.
+ * It handles specific exceptions and returns appropriate HTTP responses.
+ */
 @ControllerAdvice
 public class GlobalExceptionHandler {
+
+    /**
+     * Handles {@link ResourceNotFoundException} exceptions.
+     * This method is triggered when a {@code ResourceNotFoundException} is thrown in the application.
+     * It constructs an {@link ErrorDetails} object containing the exception details and returns
+     * a {@link ResponseEntity} with an HTTP status of {@code 404 Not Found}.
+     *
+     * @param ex the exception that was thrown.
+     * @param request the current web request in which the exception was thrown.
+     * @return a {@link ResponseEntity} containing the {@link ErrorDetails} and an HTTP status of {@code 404 Not Found}.
+     */
     @ExceptionHandler(ResourceNotFoundException.class)
     public ResponseEntity<?> resourceNotFoundException(ResourceNotFoundException ex, WebRequest request) {
         ErrorDetails errorDetails = new ErrorDetails(new Date(), ex.getMessage(), request.getDescription(false));
diff --git a/src/main/java/com/libraryman_api/controller/MemberController.java b/src/main/java/com/libraryman_api/controller/MemberController.java
index 85afc93..36c7218 100644
--- a/src/main/java/com/libraryman_api/controller/MemberController.java
+++ b/src/main/java/com/libraryman_api/controller/MemberController.java
@@ -1,33 +1,49 @@
 package com.libraryman_api.controller;
 
-import com.libraryman_api.entity.Borrowings;
 import com.libraryman_api.entity.Members;
 import com.libraryman_api.exception.ResourceNotFoundException;
-import com.libraryman_api.service.BorrowingService;
 import com.libraryman_api.service.MemberService;
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.http.ResponseEntity;
 import org.springframework.web.bind.annotation.*;
 
 import java.util.List;
 
-
+/**
+ * REST controller for managing library members.
+ * This controller provides endpoints for performing CRUD operations on members.
+ */
 @RestController
 @RequestMapping("/api/members")
 public class MemberController {
 
     private final MemberService memberService;
+
+    /**
+     * Constructs a new {@code MemberController} with the specified {@link MemberService}.
+     *
+     * @param memberService the service to handle member-related operations
+     */
     public MemberController(MemberService memberService) {
         this.memberService = memberService;
     }
 
-
-
+    /**
+     * Retrieves a list of all library members.
+     *
+     * @return a list of {@link Members} representing all members in the library
+     */
     @GetMapping
     public List<Members> getAllMembers() {
         return memberService.getAllMembers();
     }
 
+    /**
+     * Retrieves a library member by their ID.
+     * If the member is not found, a {@link ResourceNotFoundException} is thrown.
+     *
+     * @param id the ID of the member to retrieve
+     * @return a {@link ResponseEntity} containing the found {@link Members} object
+     */
     @GetMapping("/{id}")
     public ResponseEntity<Members> getMemberById(@PathVariable int id) {
         return memberService.getMemberById(id)
@@ -35,19 +51,38 @@ public ResponseEntity<Members> getMemberById(@PathVariable int id) {
                 .orElseThrow(() -> new ResourceNotFoundException("Member not found"));
     }
 
+    /**
+     * Adds a new library member.
+     *
+     * @param member the {@link Members} object representing the new member
+     * @return the added {@link Members} object
+     */
     @PostMapping
     public Members addMember(@RequestBody Members member) {
         return memberService.addMember(member);
     }
 
+    /**
+     * Updates an existing library member.
+     * If the member is not found, a {@link ResourceNotFoundException} is thrown.
+     *
+     * @param id the ID of the member to update
+     * @param memberDetails the {@link Members} object containing the updated details
+     * @return the updated {@link Members} object
+     */
     @PutMapping("/{id}")
     public Members updateMember(@PathVariable int id, @RequestBody Members memberDetails) {
         return memberService.updateMember(id, memberDetails);
     }
 
+    /**
+     * Deletes a library member by their ID.
+     * If the member is not found, a {@link ResourceNotFoundException} is thrown.
+     *
+     * @param id the ID of the member to delete
+     */
     @DeleteMapping("/{id}")
     public void deleteMember(@PathVariable int id) {
         memberService.deleteMember(id);
     }
 }
-
diff --git a/src/main/java/com/libraryman_api/email/EmailSender.java b/src/main/java/com/libraryman_api/email/EmailSender.java
index 65e9a11..3689596 100644
--- a/src/main/java/com/libraryman_api/email/EmailSender.java
+++ b/src/main/java/com/libraryman_api/email/EmailSender.java
@@ -1,6 +1,22 @@
 package com.libraryman_api.email;
+
 import com.libraryman_api.entity.Notifications;
 
+/**
+ * Interface representing an email sending service for the Library Management System.
+ * Classes implementing this interface are responsible for sending emails
+ * and updating the status of notifications in the system.
+ */
 public interface EmailSender {
-    void send (String to, String body, String subject, Notifications notification);
+
+    /**
+     * Sends an email to the specified recipient with the given body, subject, and notification details.
+     *
+     * @param to           the email address of the recipient
+     * @param body         the body of the email, typically in HTML or plain text format
+     * @param subject      the subject of the email
+     * @param notification the notification entity associated with the email being sent,
+     *                     used to track the status of the notification
+     */
+    void send(String to, String body, String subject, Notifications notification);
 }
diff --git a/src/main/java/com/libraryman_api/email/EmailService.java b/src/main/java/com/libraryman_api/email/EmailService.java
index 72a1c2a..2e2954e 100644
--- a/src/main/java/com/libraryman_api/email/EmailService.java
+++ b/src/main/java/com/libraryman_api/email/EmailService.java
@@ -13,43 +13,65 @@
 import org.springframework.scheduling.annotation.Async;
 import org.springframework.stereotype.Service;
 
-
+/**
+ * Service class for sending emails asynchronously.
+ * This class handles the construction and sending of MIME email messages.
+ */
 @Service
-public class EmailService implements EmailSender{
+public class EmailService implements EmailSender {
 
     private final NotificationRepository notificationRepository;
     private final JavaMailSender mailSender;
-    public EmailService(NotificationRepository notificationRepository, JavaMailSender mailSender) {
-        this.notificationRepository = notificationRepository;
-        this.mailSender = mailSender;
-    }
-    private final static Logger LOGGER = LoggerFactory
-            .getLogger(EmailService.class);
+
+    private static final Logger LOGGER = LoggerFactory.getLogger(EmailService.class);
 
     @Value("${spring.mail.properties.domain_name}")
     private String domainName;
 
+    /**
+     * Constructs a new {@code EmailService} with the specified {@link NotificationRepository} and {@link JavaMailSender}.
+     *
+     * @param notificationRepository the repository for managing notification entities
+     * @param mailSender the mail sender for sending email messages
+     */
+    public EmailService(NotificationRepository notificationRepository, JavaMailSender mailSender) {
+        this.notificationRepository = notificationRepository;
+        this.mailSender = mailSender;
+    }
 
+    /**
+     * Sends an email asynchronously to the specified recipient.
+     * If the email is successfully sent, the notification status is updated to SENT.
+     * If the email fails to send, the notification status is updated to FAILED and an exception is thrown.
+     *
+     * @param to the recipient's email address
+     * @param email the content of the email to send
+     * @param subject the subject of the email
+     * @param notification the {@link Notifications} object representing the email notification
+     */
     @Override
     @Async
-    public  void send(String to, String email, String subject, Notifications notification) {
+    public void send(String to, String email, String subject, Notifications notification) {
         try {
             MimeMessage mimeMessage = mailSender.createMimeMessage();
-            MimeMessageHelper helper =
-                    new MimeMessageHelper(mimeMessage, "utf-8");
+            MimeMessageHelper helper = new MimeMessageHelper(mimeMessage, "utf-8");
             helper.setText(email, true);
             helper.setTo(to);
             helper.setSubject(subject);
             helper.setFrom(domainName);
             mailSender.send(mimeMessage);
 
+            // Update notification status to SENT
             notification.setNotificationStatus(NotificationStatus.SENT);
             notificationRepository.save(notification);
         } catch (MessagingException e) {
-            LOGGER.error("failed to send email", e);
+            LOGGER.error("Failed to send email", e);
+
+            // Update notification status to FAILED
             notification.setNotificationStatus(NotificationStatus.FAILED);
             notificationRepository.save(notification);
-            throw new IllegalStateException("failed to send email");
+
+            throw new IllegalStateException("Failed to send email", e);
         }
     }
 }
diff --git a/src/main/java/com/libraryman_api/entity/Notifications.java b/src/main/java/com/libraryman_api/entity/Notifications.java
index 42c7d7b..a52ae9d 100644
--- a/src/main/java/com/libraryman_api/entity/Notifications.java
+++ b/src/main/java/com/libraryman_api/entity/Notifications.java
@@ -1,19 +1,14 @@
 package com.libraryman_api.entity;
 
 import jakarta.persistence.*;
-
-
 import java.sql.Timestamp;
 
-
 @Entity
 public class Notifications {
+
     @Id
-    @GeneratedValue(strategy = GenerationType.SEQUENCE,
-            generator = "notification_id_generator")
-    @SequenceGenerator(name = "notification_id_generator",
-            sequenceName = "notification_id_sequence",
-            allocationSize = 1)
+    @GeneratedValue(strategy = GenerationType.SEQUENCE, generator = "notification_id_generator")
+    @SequenceGenerator(name = "notification_id_generator", sequenceName = "notification_id_sequence", allocationSize = 1)
     @Column(name = "notification_id")
     private int notificationId;
 
diff --git a/src/main/java/com/libraryman_api/exception/ResourceNotFoundException.java b/src/main/java/com/libraryman_api/exception/ResourceNotFoundException.java
index 2c8c26b..24281e0 100644
--- a/src/main/java/com/libraryman_api/exception/ResourceNotFoundException.java
+++ b/src/main/java/com/libraryman_api/exception/ResourceNotFoundException.java
@@ -2,14 +2,32 @@
 
 import java.io.Serial;
 
+/**
+ * Custom exception class to handle scenarios where a requested resource
+ * is not found in the Library Management System.
+ * This exception is thrown when an operation fails to locate a resource such as
+ * a book, member, or borrowing record.
+ */
 public class ResourceNotFoundException extends RuntimeException {
+
     @Serial
     private static final long serialVersionUID = 1L;
 
+    /**
+     * Constructs a new {@code ResourceNotFoundException} with the specified detail message.
+     *
+     * @param message the detail message explaining the reason for the exception
+     */
     public ResourceNotFoundException(String message) {
         super(message);
     }
 
+    /**
+     * Constructs a new {@code ResourceNotFoundException} with the specified detail message and cause.
+     *
+     * @param message the detail message explaining the reason for the exception
+     * @param cause   the cause of the exception (which is saved for later retrieval by the {@link #getCause()} method)
+     */
     public ResourceNotFoundException(String message, Throwable cause) {
         super(message, cause);
     }
diff --git a/src/main/java/com/libraryman_api/service/BookService.java b/src/main/java/com/libraryman_api/service/BookService.java
index 3693ca5..1b497e2 100644
--- a/src/main/java/com/libraryman_api/service/BookService.java
+++ b/src/main/java/com/libraryman_api/service/BookService.java
@@ -8,27 +8,72 @@
 import java.util.List;
 import java.util.Optional;
 
+/**
+ * Service class for managing books in the LibraryMan system.
+ *
+ * <p>This service provides methods to perform CRUD operations on books, including
+ * retrieving all books, retrieving a book by its ID, adding a new book, updating
+ * an existing book, and deleting a book by its ID.</p>
+ *
+ * <p>Each method in this service interacts with the {@link BookRepository} to
+ * perform database operations.</p>
+ *
+ * <p>In the case of an invalid book ID being provided, the service throws a
+ * {@link ResourceNotFoundException}.</p>
+ *
+ * @author Ajay Negi
+ */
 @Service
 public class BookService {
 
     private final BookRepository bookRepository;
 
+    /**
+     * Constructs a new {@code BookService} with the specified {@code BookRepository}.
+     *
+     * @param bookRepository the repository to be used by this service to interact with the database
+     */
     public BookService(BookRepository bookRepository) {
         this.bookRepository = bookRepository;
     }
 
+    /**
+     * Retrieves all books from the database.
+     *
+     * @return a list of all books
+     */
     public List<Books> getAllBooks() {
         return bookRepository.findAll();
     }
 
+    /**
+     * Retrieves a book by its ID.
+     *
+     * @param bookId the ID of the book to retrieve
+     * @return an {@code Optional} containing the found book, or {@code Optional.empty()} if no book was found
+     */
     public Optional<Books> getBookById(int bookId) {
         return bookRepository.findById(bookId);
     }
 
+    /**
+     * Adds a new book to the database.
+     *
+     * @param book the book to be added
+     * @return the saved book
+     */
     public Books addBook(Books book) {
         return bookRepository.save(book);
     }
 
+    /**
+     * Updates an existing book with the given details.
+     *
+     * @param bookId the ID of the book to update
+     * @param bookDetails the new details for the book
+     * @return the updated book
+     * @throws ResourceNotFoundException if the book with the specified ID is not found
+     */
     public Books updateBook(int bookId, Books bookDetails) {
         Books book = bookRepository.findById(bookId)
                 .orElseThrow(() -> new ResourceNotFoundException("Book not found"));
@@ -42,16 +87,16 @@ public Books updateBook(int bookId, Books bookDetails) {
         return bookRepository.save(book);
     }
 
+    /**
+     * Deletes a book by its ID.
+     *
+     * @param bookId the ID of the book to delete
+     * @throws ResourceNotFoundException if the book with the specified ID is not found
+     */
     public void deleteBook(int bookId) {
         Books book = bookRepository.findById(bookId)
                 .orElseThrow(() -> new ResourceNotFoundException("Book not found"));
-        /**/
         bookRepository.delete(book);
     }
 
-
-
-
-
 }
-
diff --git a/src/main/java/com/libraryman_api/service/BorrowingService.java b/src/main/java/com/libraryman_api/service/BorrowingService.java
index b3e448c..1a1ce6e 100644
--- a/src/main/java/com/libraryman_api/service/BorrowingService.java
+++ b/src/main/java/com/libraryman_api/service/BorrowingService.java
@@ -15,6 +15,23 @@
 import java.util.List;
 import java.util.Optional;
 
+/**
+ * Service class for managing the borrowing and returning of books in the LibraryMan system.
+ *
+ * <p>This service handles the borrowing and returning processes, including calculating
+ * due dates, imposing fines for overdue returns, and managing the availability of books.
+ * It also integrates with the {@link NotificationService} to send notifications
+ * related to borrowing, returning, and fines.</p>
+ *
+ * <p>Each method interacts with the {@link BorrowingRepository} and {@link FineRepository}
+ * to perform database operations, ensuring consistency and proper transactional behavior.</p>
+ *
+ * <p>In cases where a book or borrowing record is not found, or if an operation cannot be completed
+ * (e.g., returning a book with an outstanding fine), the service throws a
+ * {@link ResourceNotFoundException}.</p>
+ *
+ * @author Ajay Negi
+ */
 @Service
 public class BorrowingService {
 
@@ -22,6 +39,15 @@ public class BorrowingService {
     private final FineRepository fineRepository;
     private final NotificationService notificationService;
     private final BookService bookService;
+
+    /**
+     * Constructs a new {@code BorrowingService} with the specified repositories and services.
+     *
+     * @param borrowingRepository the repository for managing borrowing records
+     * @param fineRepository the repository for managing fine records
+     * @param notificationService the service for sending notifications
+     * @param bookService the service for managing book records
+     */
     public BorrowingService(BorrowingRepository borrowingRepository, FineRepository fineRepository, NotificationService notificationService, BookService bookService) {
         this.borrowingRepository = borrowingRepository;
         this.fineRepository = fineRepository;
@@ -29,14 +55,37 @@ public BorrowingService(BorrowingRepository borrowingRepository, FineRepository
         this.bookService = bookService;
     }
 
+    /**
+     * Retrieves all borrowings from the database.
+     *
+     * @return a list of all borrowings
+     */
     public List<Borrowings> getAllBorrowings() {
         return borrowingRepository.findAll();
     }
 
+    /**
+     * Retrieves a borrowing record by its ID.
+     *
+     * @param borrowingId the ID of the borrowing to retrieve
+     * @return an {@code Optional} containing the found borrowing, or {@code Optional.empty()} if no borrowing was found
+     */
     public Optional<Borrowings> getBorrowingById(int borrowingId) {
         return borrowingRepository.findById(borrowingId);
     }
 
+    /**
+     * Manages the borrowing process for a book.
+     *
+     * <p>This method is synchronized to ensure thread safety and is marked as
+     * {@link Transactional} to ensure that all database operations complete successfully
+     * or roll back in case of any errors. It updates the book's availability, sets the
+     * borrowing and due dates, and sends notifications related to the borrowing.</p>
+     *
+     * @param borrowing the borrowing details provided by the user
+     * @return the saved borrowing record
+     * @throws ResourceNotFoundException if the book is not found or if there are not enough copies available
+     */
     @Transactional
     public synchronized Borrowings borrowBook(Borrowings borrowing) {
         Optional<Books> book = bookService.getBookById(borrowing.getBook().getBookId());
@@ -62,7 +111,17 @@ public synchronized Borrowings borrowBook(Borrowings borrowing) {
         }
     }
 
-//    @Transactional
+    /**
+     * Manages the return process for a borrowed book.
+     *
+     * <p>This method is synchronized to ensure thread safety. It checks for overdue returns,
+     * imposes fines if necessary, and updates the book's availability. Notifications are sent
+     * for fines and successful returns. If a fine is imposed, the book cannot be returned until
+     * the fine is paid.</p>
+     *
+     * @param borrowingId the ID of the borrowing record
+     * @throws ResourceNotFoundException if the borrowing record is not found, if the book has already been returned, or if there are outstanding fines
+     */
     public synchronized void returnBook(int borrowingId) {
         Borrowings borrowing = getBorrowingById(borrowingId)
                 .orElseThrow(() -> new ResourceNotFoundException("Borrowing not found"));
@@ -88,15 +147,28 @@ public synchronized void returnBook(int borrowingId) {
         borrowingRepository.save(borrowing);
     }
 
+    /**
+     * Imposes a fine on a borrowing for overdue returns.
+     *
+     * @param borrowing the borrowing record with an overdue return
+     * @return the saved fine record
+     */
     private Fines imposeFine(Borrowings borrowing) {
         Fines fine = new Fines();
-//        fine.setAmount(BigDecimal.valueOf(10)); // Hard Coding fine for testing purpose
         fine.setAmount(calculateFineAmount(borrowing));
         return fineRepository.save(fine);
     }
 
-
-
+    /**
+     * Processes the payment of a fine associated with a borrowing.
+     *
+     * <p>If the fine is successfully paid, a notification is sent. The borrowing and fine
+     * records are updated in the database.</p>
+     *
+     * @param borrowingId the ID of the borrowing record with the fine
+     * @return a confirmation string indicating the fine has been paid
+     * @throws ResourceNotFoundException if the borrowing record is not found or if there is no outstanding fine
+     */
     public String payFine(int borrowingId) {
         Borrowings borrowing = getBorrowingById(borrowingId)
                 .orElseThrow(() -> new ResourceNotFoundException("Borrowing not found"));
@@ -113,7 +185,18 @@ public String payFine(int borrowingId) {
         return "PAID";
     }
 
-
+    /**
+     * Updates the number of available copies of a book in the library.
+     *
+     * <p>This method increases or decreases the number of copies based on the specified operation.
+     * If there are not enough copies available for a removal operation, or if the book is not found,
+     * a {@link ResourceNotFoundException} is thrown.</p>
+     *
+     * @param bookId the ID of the book to update
+     * @param operation the operation to perform ("ADD" to increase, "REMOVE" to decrease)
+     * @param numberOfCopies the number of copies to add or remove
+     * @throws ResourceNotFoundException if the book is not found or if there are not enough copies to remove
+     */
     public void updateBookCopies(int bookId, String operation, int numberOfCopies) {
         Optional<Books> book = bookService.getBookById(bookId);
 
@@ -133,22 +216,42 @@ public void updateBookCopies(int bookId, String operation, int numberOfCopies) {
         }
     }
 
+    /**
+     * Calculates the due date for a borrowing.
+     *
+     * @return the calculated due date, which is 15 days from the current date
+     */
     private Date calculateDueDate() {
         Calendar calendar = Calendar.getInstance();
         calendar.add(Calendar.DAY_OF_YEAR, 15);
         return calendar.getTime();
     }
 
+    /**
+     * Calculates the fine amount for an overdue borrowing.
+     *
+     * <p>The fine is calculated based on the number of overdue days multiplied by a fixed
+     * rate of 10 rupees per day.</p>
+     *
+     * @param borrowing the borrowing record for which the fine is being calculated
+     * @return the calculated fine amount
+     */
     private BigDecimal calculateFineAmount(Borrowings borrowing) {
         long overdueDays = ChronoUnit.DAYS.between(
                 borrowing.getDueDate().toInstant(),
                 new Date().toInstant());
         System.out.println("Over Due Days" + overdueDays);
-        System.out.println("Fine Amount" + (overdueDays*10));
+        System.out.println("Fine Amount" + (overdueDays * 10));
         return BigDecimal.valueOf(overdueDays * 10); // 10 rupees per day fine
     }
 
-
+    /**
+     * Retrieves all borrowings associated with a specific member.
+     *
+     * @param memberId the ID of the member whose borrowings are to be retrieved
+     * @return a list of borrowings associated with the specified member
+     * @throws ResourceNotFoundException if the member has not borrowed any books
+     */
     public List<Borrowings> getAllBorrowingsOfMember(int memberId) {
         return borrowingRepository.findByMember_memberId(memberId).orElseThrow(() -> new ResourceNotFoundException("Member didn't borrow any book"));
     }
diff --git a/src/main/java/com/libraryman_api/service/MemberService.java b/src/main/java/com/libraryman_api/service/MemberService.java
index 77b8caf..af60bad 100644
--- a/src/main/java/com/libraryman_api/service/MemberService.java
+++ b/src/main/java/com/libraryman_api/service/MemberService.java
@@ -1,40 +1,91 @@
 package com.libraryman_api.service;
 
 import com.libraryman_api.entity.Members;
-import com.libraryman_api.entity.Notifications;
 import com.libraryman_api.exception.ResourceNotFoundException;
 import com.libraryman_api.repository.MemberRepository;
-import com.libraryman_api.repository.NotificationRepository;
-import org.springframework.beans.factory.annotation.Autowired;
 import org.springframework.stereotype.Service;
 import java.util.List;
 import java.util.Optional;
 
+/**
+ * Service class responsible for managing member-related operations in the LibraryMan system.
+ *
+ * <p>This service provides methods for retrieving, adding, updating, and deleting member records.
+ * It integrates with the {@link NotificationService} to send notifications related to member
+ * activities such as account creation, updates, and deletions.</p>
+ *
+ * <p>Each method interacts with the {@link MemberRepository} to perform database operations, ensuring
+ * proper transactional behavior and consistency.</p>
+ *
+ * <p>In cases where a member record is not found, the service throws a
+ * {@link ResourceNotFoundException} to indicate the error.</p>
+ *
+ * @author Ajay Negi
+ */
 @Service
 public class MemberService {
 
     private final MemberRepository memberRepository;
     private final NotificationService notificationService;
+
+    /**
+     * Constructs a new {@code MemberService} with the specified repositories and services.
+     *
+     * @param memberRepository the repository for managing member records
+     * @param notificationService the service for sending notifications related to member activities
+     */
     public MemberService(MemberRepository memberRepository, NotificationService notificationService) {
         this.memberRepository = memberRepository;
         this.notificationService = notificationService;
     }
 
+    /**
+     * Retrieves all members from the database.
+     *
+     * @return a list of all members
+     */
     public List<Members> getAllMembers() {
         return memberRepository.findAll();
     }
 
+    /**
+     * Retrieves a member record by its ID.
+     *
+     * @param memberId the ID of the member to retrieve
+     * @return an {@code Optional} containing the found member, or {@code Optional.empty()} if no member was found
+     */
     public Optional<Members> getMemberById(int memberId) {
         return memberRepository.findById(memberId);
     }
 
+    /**
+     * Adds a new member to the library system.
+     *
+     * <p>This method saves the new member record in the database and sends a notification
+     * about the account creation.</p>
+     *
+     * @param member the member details to be added
+     * @return the saved member record
+     */
     public Members addMember(Members member) {
-       Members CurrentMember =  memberRepository.save(member);
-        notificationService.accountCreatedNotification(CurrentMember);
+        Members currentMember = memberRepository.save(member);
+        notificationService.accountCreatedNotification(currentMember);
 
-        return CurrentMember;
+        return currentMember;
     }
 
+    /**
+     * Updates an existing member's details.
+     *
+     * <p>This method updates the member's details in the database. It throws a
+     * {@link ResourceNotFoundException} if the member is not found. After updating,
+     * a notification about the account details update is sent.</p>
+     *
+     * @param memberId the ID of the member to update
+     * @param memberDetails the updated member details
+     * @return the updated member record
+     * @throws ResourceNotFoundException if the member is not found
+     */
     public Members updateMember(int memberId, Members memberDetails) {
         Members member = memberRepository.findById(memberId)
                 .orElseThrow(() -> new ResourceNotFoundException("Member not found"));
@@ -43,18 +94,29 @@ public Members updateMember(int memberId, Members memberDetails) {
         member.setPassword(memberDetails.getPassword());
         member.setRole(memberDetails.getRole());
         member.setMembershipDate(memberDetails.getMembershipDate());
-        member =  memberRepository.save(member);
+        member = memberRepository.save(member);
         notificationService.accountDetailsUpdateNotification(member);
         return member;
     }
 
+    /**
+     * Deletes a member from the library system.
+     *
+     * <p>This method deletes the member record from the database after ensuring that
+     * the member has no outstanding fines or borrowed books. Before deletion, it
+     * sends a notification about the account deletion.</p>
+     *
+     * @param memberId the ID of the member to delete
+     * @throws ResourceNotFoundException if the member is not found
+     */
     public void deleteMember(int memberId) {
         Members member = memberRepository.findById(memberId)
                 .orElseThrow(() -> new ResourceNotFoundException("Member not found"));
 
-        // write logic to check if there is any fine or any book to return. If there is nothing, then delete all notification, borrow, fine
+        // TODO: Implement logic to check if the member has any outstanding fines or borrowed books.
+        // If there are no pending obligations, delete all related notifications, borrowings, and fines.
+
         notificationService.accountDeletionNotification(member);
         memberRepository.delete(member);
     }
 }
-
diff --git a/src/main/java/com/libraryman_api/service/NotificationService.java b/src/main/java/com/libraryman_api/service/NotificationService.java
index 1bb0ada..7436b36 100644
--- a/src/main/java/com/libraryman_api/service/NotificationService.java
+++ b/src/main/java/com/libraryman_api/service/NotificationService.java
@@ -8,24 +8,42 @@
 import org.springframework.stereotype.Service;
 import java.sql.Timestamp;
 
-
+/**
+ * Service class responsible for managing notifications within the LibraryMan application.
+ * This service handles various notification-related tasks, such as sending email notifications
+ * for account creation, deletion, borrowing books, returning books, fines, and account updates.
+ * It interacts with the {@link NotificationRepository}, {@link MemberRepository}, and {@link EmailSender}
+ * to perform these tasks.
+ */
 @Service
 public class NotificationService {
     private final EmailSender emailSender;
     private final NotificationRepository notificationRepository;
     private final MemberRepository memberRepository;
+
+    /**
+     * Constructs a new {@code NotificationService} with the specified {@link EmailSender},
+     * {@link NotificationRepository}, and {@link MemberRepository}.
+     *
+     * @param emailSender            the service responsible for sending emails.
+     * @param notificationRepository the repository to manage notifications in the database.
+     * @param memberRepository       the repository to manage members in the database.
+     */
     public NotificationService(EmailSender emailSender, NotificationRepository notificationRepository, MemberRepository memberRepository) {
         this.emailSender = emailSender;
         this.notificationRepository = notificationRepository;
         this.memberRepository = memberRepository;
     }
 
-
-
+    /**
+     * Sends a notification to a member when their account is created.
+     *
+     * @param members the member whose account has been created.
+     */
     public void accountCreatedNotification(Members members) {
         Notifications notification = new Notifications();
         notification.setMember(members);
-        notification.setMessage("We’re excited to welcome you to LibraryMan! Your account has been successfully created, and you’re now part of our community of book lovers. \uD83D\uDCDA<br><br>Feel free to explore our vast collection of books and other resources. If you have any questions or need assistance, our team is here to help.<br><br>Happy reading!  \uD83D\uDCD6");
+        notification.setMessage("We’re excited to welcome you to LibraryMan! Your account has been successfully created, and you’re now part of our community of book lovers. 📚<br><br>Feel free to explore our vast collection of books and other resources. If you have any questions or need assistance, our team is here to help.<br><br>Happy reading! 📖");
         notification.setNotificationType(NotificationType.ACCOUNT_CREATED);
         notification.setSentDate(new Timestamp(System.currentTimeMillis()));
 
@@ -33,6 +51,11 @@ public void accountCreatedNotification(Members members) {
         notificationRepository.save(notification);
     }
 
+    /**
+     * Sends a notification to a member when their account is deleted.
+     *
+     * @param members the member whose account has been deleted.
+     */
     public void accountDeletionNotification(Members members) {
         Notifications notification = new Notifications();
         notification.setMember(members);
@@ -42,16 +65,20 @@ public void accountDeletionNotification(Members members) {
         sendNotification(notification);
     }
 
-
+    /**
+     * Sends a notification to a member when they borrow a book.
+     *
+     * @param borrowing the borrowing instance containing information about the borrowed book.
+     */
     public void borrowBookNotification(Borrowings borrowing) {
         Notifications notification = new Notifications();
         notification.setMember(borrowing.getMember());
-        notification.setMessage("Congratulations! \uD83C\uDF89 You have successfully borrowed '" +
-                borrowing.getBook().getTitle() + " book on " + // This is passing null value. correct it
+        notification.setMessage("Congratulations! 🎉 You have successfully borrowed '" +
+                borrowing.getBook().getTitle() + "' on " +
                 borrowing.getBorrowDate() +
                 ".<br><br>You now have 15 days to enjoy reading it. We kindly request that you return it to us on or before " +
                 borrowing.getDueDate() +
-                " to avoid any late fees \uD83D\uDCC6, which are ₹10 per day for late returns.<br><br>If you need to renew the book or have any questions, please don't hesitate to reach out to us.<br><br>Thank you for choosing our library!");
+                " to avoid any late fees 📆, which are ₹10 per day for late returns.<br><br>If you need to renew the book or have any questions, please don't hesitate to reach out to us.<br><br>Thank you for choosing our library!");
         notification.setNotificationType(NotificationType.BORROW);
         notification.setSentDate(new Timestamp(System.currentTimeMillis()));
 
@@ -59,17 +86,20 @@ public void borrowBookNotification(Borrowings borrowing) {
         notificationRepository.save(notification);
     }
 
-
+    /**
+     * Sends a reminder notification to a member when the due date for returning a borrowed book is approaching.
+     *
+     * @param borrowing the borrowing instance containing information about the borrowed book.
+     */
     public void reminderNotification(Borrowings borrowing) {
         Notifications notification = new Notifications();
         notification.setMember(borrowing.getMember());
         notification.setMessage("This is a friendly reminder that the due date to return '" +
-                borrowing.getBook().getTitle()  + // This is passing null value. correct it
-                "' book is approaching. Please ensure that you return the book by " +
+                borrowing.getBook().getTitle() + "' is approaching. Please ensure that you return the book by " +
                 borrowing.getBorrowDate() +
-                " to avoid any late fees. \uD83D\uDCC5" +
+                " to avoid any late fees. 📅" +
                 "<br><br>If you need more time, consider renewing your book through our online portal or by contacting us." +
-                "<br><br>Thank you, and happy reading! \uD83D\uDE0A");
+                "<br><br>Thank you, and happy reading! 😊");
         notification.setNotificationType(NotificationType.REMINDER);
         notification.setSentDate(new Timestamp(System.currentTimeMillis()));
 
@@ -77,13 +107,17 @@ public void reminderNotification(Borrowings borrowing) {
         notificationRepository.save(notification);
     }
 
+    /**
+     * Sends a notification to a member when they pay a fine for an overdue book.
+     *
+     * @param borrowing the borrowing instance containing information about the overdue book and the fine paid.
+     */
     public void finePaidNotification(Borrowings borrowing) {
         Notifications notification = new Notifications();
         notification.setMember(borrowing.getMember());
         notification.setMessage("Thank you for your payment. We’ve received your payment of ₹" +
-                borrowing.getFine().getAmount() + " towards the fine for the overdue return of '" + borrowing.getBook().getTitle()  + "' book. ✅" +
-                "<br><br>Your account has been updated accordingly. If you have any questions or need further assistance, please feel free to reach out.\n" +
-                "<br><br>Thank you for your prompt payment.");
+                borrowing.getFine().getAmount() + " towards the fine for the overdue return of '" + borrowing.getBook().getTitle() + "'. ✅" +
+                "<br><br>Your account has been updated accordingly. If you have any questions or need further assistance, please feel free to reach out.<br><br>Thank you for your prompt payment.");
         notification.setNotificationType(NotificationType.PAID);
         notification.setSentDate(new Timestamp(System.currentTimeMillis()));
 
@@ -91,15 +125,19 @@ public void finePaidNotification(Borrowings borrowing) {
         notificationRepository.save(notification);
     }
 
-
+    /**
+     * Sends a notification to a member when a fine is imposed for the late return of a borrowed book.
+     *
+     * @param borrowing the borrowing instance containing information about the overdue book and the fine imposed.
+     */
     public void fineImposedNotification(Borrowings borrowing) {
         Notifications notification = new Notifications();
         notification.setMember(borrowing.getMember());
         notification.setMessage("We hope you enjoyed reading '" +
                 borrowing.getBook().getTitle() +
-                "' book. Unfortunately, our records show that the book was returned after the due date of " +
+                "'. Unfortunately, our records show that the book was returned after the due date of " +
                 borrowing.getDueDate() +
-                " . As a result, a fine of ₹10 per day has been imposed for the late return.<br><br>The total fine amount for this overdue return is ₹" +
+                ". As a result, a fine of ₹10 per day has been imposed for the late return.<br><br>The total fine amount for this overdue return is ₹" +
                 borrowing.getFine().getAmount() +
                 ".<br><br>If you have any questions or would like to discuss this matter further, please don't hesitate to contact us.<br><br>Thank you for your understanding and for being a valued member of our library.");
         notification.setNotificationType(NotificationType.FINE);
@@ -109,7 +147,11 @@ public void fineImposedNotification(Borrowings borrowing) {
         notificationRepository.save(notification);
     }
 
-
+    /**
+     * Sends a notification to a member when their account details are updated.
+     *
+     * @param members the member whose account details have been updated.
+     */
     public void accountDetailsUpdateNotification(Members members) {
         Notifications notification = new Notifications();
         notification.setMember(members);
@@ -122,10 +164,15 @@ public void accountDetailsUpdateNotification(Members members) {
         notificationRepository.save(notification);
     }
 
+    /**
+     * Sends a notification to a member when they return a borrowed book.
+     *
+     * @param borrowing the borrowing instance containing information about the returned book.
+     */
     public void bookReturnedNotification(Borrowings borrowing) {
         Notifications notification = new Notifications();
         notification.setMember(borrowing.getMember());
-        notification.setMessage("Thank you for returning '" + borrowing.getBook().getTitle() + "' book on " + borrowing.getReturnDate() + ". We hope you enjoyed the book!" +
+        notification.setMessage("Thank you for returning '" + borrowing.getBook().getTitle() + "' on " + borrowing.getReturnDate() + ". We hope you enjoyed the book!" +
                 "<br><br>Feel free to explore our collection for your next read. If you have any questions or need assistance, we’re here to help." +
                 "<br><br>Thank you for choosing LibraryMan!");
         notification.setNotificationType(NotificationType.RETURNED);
@@ -135,7 +182,11 @@ public void bookReturnedNotification(Borrowings borrowing) {
         notificationRepository.save(notification);
     }
 
-
+    /**
+     * Sends the notification email to the member.
+     *
+     * @param notification the notification instance containing information about the notification.
+     */
     private void sendNotification(Notifications notification) {
         Members member = memberRepository.findByMemberId(notification.getMember().getMemberId())
                 .orElseThrow(() -> new ResourceNotFoundException("Member not found"));
@@ -152,20 +203,46 @@ private void sendNotification(Notifications notification) {
         );
     }
 
-    private String subject(NotificationType notificationType) {
-        return switch (notificationType) {
-            case ACCOUNT_CREATED -> "Welcome to LibraryMan! \uD83C\uDF89";
-            case ACCOUNT_DELETED -> "Account Deletion Confirmation 🗑️";
-            case BORROW -> "Book Borrowed Successfully \uD83C\uDF89";
-            case REMINDER -> "Reminder: Due date approaching ⏰";
-            case PAID -> "Payment Received for Fine \uD83D\uDCB8";
-            case FINE -> "Overdue Fine Imposed ‼️";
-            case UPDATE -> "Account Details Updated \uD83D\uDD04";
-            case RETURNED -> "Book Returned Successfully \uD83D\uDCDA";
-        };
+    /**
+     * Builds the email content based on the notification type, member name, and notification message.
+     *
+     * @param notificationType   the type of notification.
+     * @param memberName         the name of the member.
+     * @param notificationMessage the notification message to include in the email.
+     * @return the built email content.
+     */
+    private String buildEmail(NotificationType notificationType, String memberName, String notificationMessage) {
+        return "Hello " + memberName + ",<br><br>" + notificationMessage + "<br><br>" + "Best regards,<br>The LibraryMan Team";
     }
 
-
+    /**
+     * Determines the subject line for the email based on the notification type.
+     *
+     * @param notificationType the type of notification.
+     * @return the subject line for the email.
+     */
+    private String subject(NotificationType notificationType) {
+        switch (notificationType) {
+            case ACCOUNT_CREATED:
+                return "Welcome to LibraryMan!";
+            case ACCOUNT_DELETED:
+                return "Your LibraryMan Account has been Deleted";
+            case BORROW:
+                return "Book Borrowed Successfully";
+            case REMINDER:
+                return "Reminder: Book Due Date Approaching";
+            case PAID:
+                return "Payment Received";
+            case FINE:
+                return "Fine Imposed for Late Return";
+            case RETURNED:
+                return "Thank You for Returning Your Book";
+            case UPDATE:
+                return "Your Account Details Have Been Updated";
+            default:
+                return "LibraryMan Notification";
+        }
+    }
 
 
     private String buildEmail(String notificationType,String memberName, String notificationMessage) {
@@ -239,6 +316,7 @@ private String buildEmail(String notificationType,String memberName, String noti
                 "  </tbody></table><div class=\"yj6qo\"></div><div class=\"adL\">\n" +
                 "\n" +
                 "</div></div>";
+
     }
 
 }
diff --git a/src/main/resources/application-development.properties b/src/main/resources/application-development.properties
index b757e3b..94719e8 100644
--- a/src/main/resources/application-development.properties
+++ b/src/main/resources/application-development.properties
@@ -2,6 +2,8 @@
 
 ## Create a Database and add database name where "Add_Your_Database_Name" is below
 ## Make this file as it was earlier before commiting code
+
+# Change this connection string to this format: jdbc:mysql://{ip_address}:{port}/{database_name}
 spring.datasource.url=jdbc:mysql://localhost:3306/Add_Your_Database_Name
 
 ## Add your Database Username and Password
@@ -10,4 +12,6 @@ spring.datasource.password= Add_Your_Password
 
 spring.datasource.driver-class-name=com.mysql.cj.jdbc.Driver
 spring.jpa.hibernate.ddl-auto=update
-spring.jpa.show-sql=true
\ No newline at end of file
+spring.jpa.show-sql=true
+
+logging.level.org.springframework.security = TRACE
\ No newline at end of file