Var
The var is a keyword that is used to declare a variable,We can declare a variable again even if it has been defined previously in the same scope.
syntax
var name = value;let
The let is also a keyword that is used to declare a variable, We cannot declare a variable more than once if we defined that previously in the same scope.
syntax
let name = value;Const
The value of a constant can’t be changed through reassignment (i.e. by using the assignment operator), and it can’t be redeclared
syntax
const VARIABLE_NAME = value;
