Relation between classes

Game playing screen

What i learned from this project

• object

what is object and how to make object (object literal and consturctor)

• global variable

reasons to avoid global variables and how to replace them (In this project, i use es6 module)

• this & bind(this)

what is 'this' and how can control 'this' by progammer

• prototype chain

change object property by changine prototype object