2-variables.html

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    <title>variables in javaScript</title>
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    <script>
        // rules for javaScript variables:
        // 1: starting with number will not allow 
        // example: let 1ali= 65;
        // 2: javaScript reserved word cannot used as variables
        // 3: javaScript is caseSencsitive 
        
        var x=3;
        var y=5;
        console.log(x);
        console.log(y);
       // for declering variables we use var,let,const

        // mostly we avoid the var in programming due to it may be creat some bugs 
        // so we prefer to use let and const variables 
        
        // we have 7 types of premitive datatypes in javaScript 
        // datatypes means which type of data we can store in variables
        // NNSSBBU= null,number,symbol,string,boolean,bigint and undefind these are the seven datatypes
          // premitive datatype example:

          let a=null;
          let b=5;
          let c=Symbol("i am a symbol");
          let d="saleem";
          let e=true;
          let f=BigInt("889")+ BigInt("999");
          let g // this is undefined;
          console.log(a,b,c,d,e,f,g);


    </script>
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