diff --git a/docs/UserGuide.md b/docs/UserGuide.md
index 666e229a97d..8483b8ce6c2 100644
--- a/docs/UserGuide.md
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@@ -779,13 +779,14 @@ Exits the program.
## Glossary
-| Term | Definition |
-|------|------------|
-| **Top Level Domain** | A Top Level Domain (TLD) is the part of the website address where it comes after the last dot (i.e. ".com", ".org", ".net") and before the first slash. (E.g. www.example.**com**/path). |
-| **Whitespace** | In the context of this application, a whitespace is any number of spaces or tabs that is in the input. |
-| **Contact** | A contact in Jobby is can be an **organization** or a **recruiter**. |
-| **Substring** | A substring is a contiguous sequence of characters within a string.
e.g. "pp" is a substring of "apple", "mac" is a substring of "macDonald" and "intimacy" |
-
+| Term | Definition |
+|----------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
+| **Index** | An index is a number that is used to identify a contact or job application in a list.
(e.g. `2` would be the index of the contact labelled **2.** in the contacts list). |
+| **Whitespace** | In the context of this application, a whitespace is any number of spaces that is in the input. |
+| **Contact** | A contact in Jobby is can be an Organization or a Recruiter. |
+| **Substring** | A substring is a contiguous sequence of characters within a string.
(e.g. "pp" is a substring of "apple", "mac" is a substring of "macDonald" and "intimacy") |
+| **Subsequence** | A subsequence is a sequence obtainable from another sequence by deleting some or no elements without changing the order of the remaining elements
(e.g. "abc", "1b2", "123" are all subsequences of "a1b2c3"). |
+| **Top Level Domain** | A Top Level Domain (TLD) is the part of the website address where it comes after the last dot (i.e. ".com", ".org", ".net") and before the first slash
(e.g. www.example.**com**/path). |
## Appendices