Java script

what is javascript ?

1. It is a programming language of the web pages.
2. It is updated and change both HTML and CSS.
3. It can calculated ,manipulate and validate data.

what is javascript variables ?

1. Java script variables is used to the store data values.
2. Java script uses the keywords likes var,let,const to declare variables.

what is var ?

1. Only use var if you MUST support old browsers.
2. The var keyword was used in all JavaScript code from 1995 to 2015.
3. Variables declared with the var always have Global Scope.

what is let ?

1. The let declaration declares re-assignable, block-scoped local variables, optionally initializing each to a value.
2. The let keyword was introduced in ES6 (2015).

what is const ?

1. The const keyword was introduced in ES6 (2015).
2. Variables defined with const cannot be Redeclared.
3. Variables defined with const cannot be Reassigned.
4. Variables defined with const have Block Scope.