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We can declare multiple variables in the same line in the following way:

                    var firstName = "Priya", age = 22, city = "Delhi";
                 Declaration
                 Declaration means creating a variable, essentially giving it a name, so the program knows it exists.

                 In JavaScript, this is done using var, let, or const. When you declare a variable, it doesn’t necessarily hold a
                 value yet.
                    var name;   // Declaring a variable named 'name'
                    var age;    // Declaring a variable named 'age'
                    const PI;   // Error: const must be initialized immediately
                             Notes


                             Let and var can declare without initialization. const must be initialized during declaration.



                 Initialization
                 Initialization means assigning a value to a declared variable for the first time. The equal to (=) sign is used to
                 assign a value to a variable.

                 In JavaScript, you can initialize a variable either during the declaration or later on.
                    var name = "Aryan";                 // Declaration + Initialization
                    var age = 25;              // Declaration + Initialization
                    const PI = 3.14;           // Declaration + Initialization
                    //const must be initialized immediately
                 The value and data type of a variable can change during the execution of a program and JavaScript takes care
                 of it automatically.
                 Variable Naming Conventions

                 In JavaScript,  following  proper  variable  naming  conventions is essential for  making code  clearer,  more
                 readable, and easier to maintain.

                 Some rules and best practices for naming variables in JavaScript are as follows:
                   Camel Case Notation: JavaScript variables are typically written in camelCase. The first word starts with a
                    lowercase letter, and each subsequent word starts with an uppercase letter.
                    For example:
                    var firstName= "Rahul";

                   var studentAge = 18;
                   Case Sensitivity:  JavaScript  variable  names  are  case-sensitive.  This  means  firstName,  Firstname,  and
                    firstname are all different variables.
                    For example:

                   var city = "Delhi";
                   var City = "Mumbai";
                   Descriptive Names: Use meaningful names that describe the value the variable holds or the purpose it serves.

                    For example:
                   var userScore = 95; // good
                   var x= 95; // not descriptive

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