What I learn today.
This keyword holds the reference of an object that defines the current line of execution.
The new keyword is used to create an instance of an object, Its create a new empty object.
A variable that declares outside of a function that is a global variable. A global variable can access from anywhere in the program.
== vs ===
== is compare two values where === compare two values as well as datatype.
The closure is the combination of a function that bundled together with references of its surrounding state. In other words, closure gives access of the outer function scope from the inner function.
It is a technique where a function call over and over from that function itself until it reached the result.