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STATEMENTS IN JAVASCRIPT


            Commands  and instructions  given to  the
            JavaScript interpreter to take some actions
                                                                            Subject: The confirm( ) Method
            are called  statements and a collection  of
                                                                            The confirm() method displays a dialog
            statements is called a script or a program.                     box  with  a  specified  message,  along
            Within  almost  every browser resides                           with an OK and a Cancel button.
            the  JavaScript  interpreter.  We  use  the
            semicolon to terminate a statement but, if
            the statements are written in separate lines, then the semicolon can be omitted.

            JavaScript statements consist of keywords, variables, operators, expressions and comments.
            Let us learn about them in detail.

            KEYWORDS

            A keyword is a reserved word that has a special meaning for the JavaScript interpreter. Some of
            the keywords of JavaScript are:

                                    var,  switch,  let,  for, const,  function,  if,  return, etc.

            VARIABLES

            A variable is the name of storage location. It stores a value that can be modified later. JavaScript
            is a loosely typed language which means it does not require a data type to be declared before
            using it. Syntax to declare a variable in JavaScript is:

            var <variable name> = <value>;
            where var is a keyword, <variable name> is a valid name for the variable and <value> is the value
            that you want to assign the variable.
            For example:

            var age = 16;
            var name = "A"
            We can declare multiple variables in the same line in the following way:

            var v1 = 1, v2 = "Delhi", v3;

            Variable Naming Conventions

            Some of the naming conventions that need to be followed while declaring variables in JavaScript are:
                Variable names are case-sensitive which means that the variable name 'AGE' is different from
              'age'.

                A variable name must not start with digits 0–9.
                Variable names can contain letters, digits, or the symbols $ and _.
                A variable name cannot be a reserved keyword.




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