JS Learning Comb (c) Type and grammar

2. Type
   • JavaScript has seven built-in types: null, Undefined, Boolean, number, String, object, and symbol, and you can use the TypeOf operator to view
   • typeof returns all strings.
   • Many developers confuse undefined and undeclared, but they are different in JavaScript. Undefined is one of the values. Undeclared indicates that the variable has not been declared.
3. Value
   The
   • string reverses the

      var  a = "foo"  var  C = a    Convert the value of a to a character array . Split (")  //  .reverse ()  // . Join (" //
       "Oof"  

   • smaller numeric comparison

      function   Numberscloseenoughtoequal (n1,n2) { return  Math.Abs (n1-n2) < Number.epsilon;}  

   • security range for integers

JS Learning to Comb (c) type and grammar