What is JavaScript ?

Is the programming language of the Web, enables you to create daynamic updating content, control multimedia, animate images and pretty everythings, it executed line by line and have the .js extension.

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## Variables :

Can store data in variables.

Syntax

var VarName(should be a valid identifier) = variable value ;

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## JavaScript Data Types :

• Number :

   var age= 24;
  

• String :

   var name="saja" // double cotation.
   var name='saja' // single cotation.
  

• Boolean :

  var ischecked= true or false;
  

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JavaScript Output :

• Using console.log()

  console.log(‘first name’ + fname)

• Using document.write()

  document.write(‘first name’ + fname)

• Using alert() (message box)

  alert(‘what your name’)

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JavaScript Comments :

Using comments to prevent execution

• Single line comments start with // .
• multi line comment start with /* and end with */ .

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Window prompt() Method :

Display a prompt box which ask the user for anythings like name , age , etc .

var fname= prompt("Please enter your name", "your name");

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JavaScript if else :

Are used to do different actions based on different conditions.

if(condition==true)
{
    // do some thing if true 

    else
    {
       // do some thimg if not true 
    }
}

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