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      Reserved Keywords

      JavaScript Tutorial

      This JavaScript tutorial is crafted for beginners to introduce them to the basics and advanced concepts of JavaScript. By the end of this guide, you'll reach a proficiency level that sets the stage for further growth. Aimed at empowering you to progress towards becoming a world-class software developer, this tutorial paves the way for a successful career in web development and beyond.

      Reserved Keywords

      Reserved Keywords in JavaScript

      Reserved keywords in JavaScript are predefined words that serve specific purposes within the language. They are reserved for use by the JavaScript engine and cannot be redefined or used for any other purpose in your code.
      Some examples of reserved keywords in JavaScript include let, const, function, if, else, return, and many more.
      
      For example, if you try to declare a variable with a name that is a reserved keyword like let:
      let let = 10; // SyntaxError: Unexpected token 'let'
      This will result in a syntax error because let is a reserved keyword and cannot be used as an identifier for a variable.

      Reserved Keywords

      Here is the list of reserved keywords; you can’t use them as an identifier
      abstract
      double
      implements
      return
      arguments
      else
      in
      switch
      await
      enum
      instanceof
      synchronized
      boolean
      eval
      int
      this
      break
      export
      interface
      throw
      byte
      extends
      let
      throws
      case
      false
      long
      transient
      catch
      final
      native
      true
      char
      finally
      new
      try
      class
      float
      null
      typeof
      const
      for
      package
      var
      continue
      function
      private
      void
      debugger
      goto
      protected
      volatile
      default
      if
      public
      yield
      delete
      implements
      short
      while
      do
      import
      static
      with
      double
      in
      super

      Reserved Keywords added in ES5 and ES6

      Some new keywords are added in the ES5 and ES6 versions of JavaScript. However, some are currently in use, and some keywords are reserved for future versions.
      await
      class
      enum
      export
      extends
      import
      let
      Super