In JavaScript,==and===both represent logic, etc. The difference is that:
*When doing logic and other tasks, perform type conversion first.
*If===, then it won’t.

The following example:

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<script language="javascript"> 
     var valueA = "1"; 
     var valueB = 1; 
     if ( valueA == valueB) { 
          alert("Equal"); 
     } 
      else { 
           alert("Not equal") 
      } 
      //output: "Equal"
      if ( valueA === valueB) { 
           alert("Equal"); 
      } 
      else { 
           alert("Not equal") 
      } 
      //output: "Not equal"
</script>