New Challenge Named Variables added

Author: 0vai5

web/src/pages/challenges/_meta.json

@@ -4,5 +4,6 @@
   "objects": "Objects",
   "collections": "Collections",
   "async": "Asynchronous",
-  "dom": "DOM"
+  "dom": "DOM",
+  "variables": "Variables"
 }

web/src/pages/challenges/variables.mdx

@@ -0,0 +1,205 @@
+
+# JavaScript Variables
+
+   ## Activity 1
+
+   ### Task 1: Create a Variable using var Keyword and log it to the console
+
+   **Code:**
+   ```jsx live
+   var num = 10;
+   console.log(num); // 10
+   ```
+
+   **Outcome:**
+   - The console will display `10`.
+   - The variable `num` is declared using `var` and assigned the value `10`.
+
+   ### Task 2: Create a Variable using let Keyword and log it to the console
+
+   **Code:**
+   ```jsx live
+   let Str = "Hello Chai";
+   console.log(Str); // "Hello Chai"
+   ```
+
+   **Outcome:**
+   - The console will display `Hello Chai`.
+   - The variable `Str` is declared using `let` and assigned the value `"Hello Chai"`.
+
+   ---
+
+   ## Activity 2
+
+   ### Task 3: Create a constant using const Keyword and log it to the console
+
+   **Code:**
+   ```jsx live
+   const bool = true;
+   console.log(bool); // True
+   ```
+
+   **Outcome:**
+   - The console will display `true`.
+   - The constant `bool` is declared using `const` and assigned the value `true`.
+
+   ---
+
+   ## Activity 3
+
+   ### Task 4: Make variables with different data types and print their type to the console
+
+   **Code:**
+   ```jsx live
+   let number = 10;
+   let string = "hello World";
+   let boolean = true;
+   let object = {
+       name: "Chai",
+       key: "code"
+   };
+   let array = ['Fruits', 'Chai', 'Vegetable'];
+
+   console.log(typeof number);  // number
+   console.log(typeof string);  // string
+   console.log(typeof boolean); // boolean
+   console.log(typeof object);  // object
+   console.log(typeof array);   // object (arrays are of type object in JavaScript)
+   ```
+
+   **Outcome:**
+   - The console will display:
+     ```
+     number
+     string
+     boolean
+     object
+     object
+     ```
+   - The types of the variables are printed using the `typeof` operator.
+
+   ---
+
+   ## Activity 4
+
+   ### Task 5: Declare a variable using let Keyword and assign it a value and reassign its value
+
+   **Code:**
+   ```jsx live
+   let chai = "code";
+   console.log(chai); // "code"
+   chai = "Hitesh Sir";
+   console.log(chai); // "Hitesh Sir"
+   ```
+
+   **Outcome:**
+   - The console will display:
+     ```
+     code
+     Hitesh Sir
+     ```
+   - The variable `chai` is declared using `let`, initially assigned the value `"code"`, and then reassigned the value `"Hitesh Sir"`.
+
+   ---
+
+   ## Activity 5
+
+   ### Task 6: Make a constant using const Keyword and try to reassign the value and Identify the error
+
+   **Code:**
+   ```jsx live
+   const chaiCode = "ChaiCode.com";
+   console.log(chaiCode); // "ChaiCode.com"
+   chaiCode = "www.chaicode.com"; // This line will cause an error
+   ```
+
+   **Outcome:**
+   - The console will display:
+     ```
+     ChaiCode.com
+     ```
+   - Then, it will throw an error: `TypeError: Assignment to constant variable`.
+   - The constant `chaiCode` is declared using `const` and assigned the value `"ChaiCode.com"`. Attempting to reassign it results in an error since constants cannot be reassigned.
+
+   ---
+
+   ## Feature Request 1
+
+   **Code:**
+   ```jsx live
+   let number1 = 10;
+   let string1 = "hello World";
+   let boolean1 = true;
+   let object1 = {
+       name: "Chai",
+       key: "code"
+   };
+   let array1 = ['Fruits', 'Chai', 'Vegetable'];
+
+   console.log(`${number1} is a  ${typeof number1}`);
+   console.log(`${string1} is a  ${typeof string1}`);
+   console.log(`${boolean1} is a  ${typeof boolean1}`);
+   console.log(`${object1} is a  ${typeof object1}`);
+   console.log(`${array1} is a  ${typeof array1}`);
+   ```
+
+   **Outcome:**
+   - The console will display:
+     ```
+     10 is a  number
+     hello World is a  string
+     true is a  boolean
+     [object Object] is a  object
+     Fruits,Chai,Vegetable is a  object
+     ```
+   - This shows the type of each variable using template literals and `typeof`.
+
+   ---
+
+   ## Feature Request 2
+
+   **Code:**
+   ```jsx live
+   let hello = "world";
+   console.log(hello);
+   hello = "Hello Chai";
+
+   const HiteshSir = 'Chai Aur Code';
+   console.log(HiteshSir);
+   HiteshSir = 'www.chaicode.com'; // This line will cause an error
+   ```
+
+   **Outcome:**
+   - The console will display:
+     ```
+     world
+     Hello Chai
+     Chai Aur Code
+     ```
+   - Then, it will throw an error: `TypeError: Assignment to constant variable`.
+   - The variable `hello` is declared using `let`, initially assigned the value `"world"`, and then reassigned the value `"Hello Chai"`.
+   - The constant `HiteshSir` is declared using `const` and assigned the value `'Chai Aur Code'`. Attempting to reassign it results in an error since constants cannot be reassigned.
+
+   ---
+
+   **Summary of Key Learnings:**
+
+   1. **Variable Declarations:**
+      - `var` declares variables with function scope or globally if declared outside a function.
+      - `let` declares variables with block scope, allowing reassignment.
+      - `const` declares variables with block scope, but they cannot be reassigned after the initial assignment.
+
+   2. **Type Checking:**
+      - The `typeof` operator is used to determine the type of a variable.
+
+   3. **Reassignment:**
+      - Variables declared with `let` can be reassigned.
+      - Constants declared with `const` cannot be reassigned, and attempting to do so results in an error.
+
+   4. **Template Literals:**
+      - Template literals (using backticks) allow embedding expressions within strings using `${expression}`.
+
+   ---
+
+   This CHallenge provides a comprehensive overview of JavaScript variables, covering variable declarations (`var`, `let`, `const`), type checking, reassignment rules, and usage examples. Each section includes code snippets, expected outcomes, and summaries of key learnings.
+