Explain Variables in Java Script?

Like any programming languages java script has variables. These are data items, that we can manipulate when the program runs. A variable is a named value that you can use in your program. 

For example x = 5; here variable name ‘x’ which is set to the value ‘5’. Most variables in the program doesn’t have fixed values.

 Rules for variable names: 

There are strick rules governing how you name your variable in java script.

1) Names must (start) begin with letter digit and underscore.

2) Cannot use white space’s in variable names.

3) Names are case sensitive, so that stu; STU; sTU; StU; all are refer to different variables.

4) Cannot use a reserved word (key word) as a variable name. reserved words are those words which are the part of the java script language.

5) Using ‘var’ key word we can create variables.

Syntax:  var variable-name;

        Eg: var a;

 Assigning data values to variables:

Syntax:  Variable–name = value;

        Eg: a = 5;

               b = “sasi”;

               c = 87.72;

Initialization of variables: Assigning the data at the time of declaration is called ‘Initialization’.

Syntax: var variable –name = value;

       Eg: var first = “surya”;

              var second = 96665;