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  Allowed Characters: Variable names can include Letters (a-z, A-Z), Digits (0-9), dollar sign ($), underscore (_).
                 However, variable names cannot start with a digit.
                 For example:

                var student_name = "Aisha"; // valid
                var 1Place = "Winner"; // invalid, starts with a number
                No  Reserved Keywords:  Variable  names cannot  be  JavaScript  reserved  words. Reserved  words (or
                 keywords) are special terms that have a predefined meaning in the language’s syntax. These words are
                 reserved for specific tasks and cannot be used as identifiers — such as variable names, function names, or
                 class names — to avoid conflicts with JavaScript’s built-in functionality.
                Constants in Upper Case: Variables that hold constant values are often written in UPPERCASE letters,
                 with underscores to separate words.
                 For example:

                 const MAX_SCORE = 100;

                const COUNTRY_NAME = "INDIA";
              JavaScript Variable Scope

              In JavaScript, variable scope determines where a variable can be accessed within your code. The two primary
              types of scope are global scope and local scope.
                Global Scope Variables: These variables are declared outside any function or block, giving them global scope.
                 This means they can be accessed from anywhere in the JavaScript code — including within functions, blocks,
                 and other parts of the program. They’re usually declared at the start of the script and remain accessible
                Local Scope Variables: These variables are declared within a function or block and have local scope. These
                 variables are only accessible within the function or block where they are defined. Function parameters are
                 also considered local variables within the function. Local variables are not accessible from outside the
                 function in which they are declared.

              JavaScript Literals
              In  JavaScript,  literals  are  fixed  values  written  directly  into  your  code.  Unlike  variables,  which  can  change
              during a program's execution, literals represent constant, unchangeable values. They form the foundation of
              JavaScript, allowing you to define different types of data — such as numbers, text, conditions, and collections
              — essential for building programs. Some different types of literals are as follows:

                Number literals represent integers or floating-point numbers.
                String literals hold textual data.
                Boolean literals represent the binary true/false logic.

                Object and array literals provide structured data formats.
                 For example:

                 var language = "French"; // String literal
                var score = 100; // Number literal (integer)

                var price  = 56.32; // Number literal (floating-point)
                var marks = [12, 24, 36]; // Array literal

                var isPassed = false; // Boolean literal

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