JavaScript Syntax

What is JavaScript Syntax?

JavaScript syntax refers to the set of rules that define how JavaScript programs are written and interpreted. It includes variables, operators, functions, statements, and expressions that control the behavior of a script.

Basic JavaScript Syntax Rules

✔ JavaScript is case-sensitive (var name ≠ var Name).
✔ Statements end with a semicolon (optional but recommended) → console.log("Hello");
✔ Curly braces {} group code blocks (e.g., functions, loops).
✔ Comments allow adding explanations (// single-line or /* multi-line */).

1️⃣ JavaScript Statements

JavaScript code is executed as a series of statements. Each statement performs an action.

Example:

let x = 10;  // Variable declaration
let y = 20;  // Another variable
let sum = x + y;  // Calculation
console.log(sum);  // Output result

✔ Effect: Displays 30 in the console.

2️⃣ JavaScript Variables

Variables store data values. JavaScript provides let, var, and const to declare variables.

Example:

let name = "John";  // String
var age = 25;       // Number
const PI = 3.14;    // Constant

✔ let is preferred over var due to better scoping rules.

3️⃣ JavaScript Data Types

JavaScript has different data types:

String: "Hello"
Number: 42
Boolean: true / false
Array: ["Apple", "Banana"]
Object: {name: "John", age: 25}

Example:

let isStudent = true;
console.log(typeof isStudent);  // Output: "boolean"

4️⃣ JavaScript Operators

Operators perform operations on variables and values.

✔ Arithmetic Operators: +, -, *, /, %, **
✔ Assignment Operators: =, +=, -=, *=, /=
✔ Comparison Operators: ==, ===, !=, !==, >, <, >=, <=
✔ Logical Operators: &&, ||, !

Example:

let a = 10;
let b = 5;
console.log(a + b);  // Output: 15
console.log(a > b);  // Output: true

5️⃣ JavaScript Functions

Functions are reusable blocks of code.

Example:

function greet() {
    return "Hello, Welcome!";
}
console.log(greet());  // Output: "Hello, Welcome!"

6️⃣ JavaScript Conditional Statements

Conditional statements allow decision-making in code.

Example (if-else):

let age = 18;
if (age >= 18) {
    console.log("You are an adult.");
} else {
    console.log("You are a minor.");
}

7️⃣ JavaScript Loops

Loops execute a block of code multiple times.

Example (for loop):

for (let i = 1; i <= 5; i++) {
    console.log("Iteration:", i);
}

✔ Effect: Prints numbers from 1 to 5.

8️⃣ JavaScript Comments

✔ Single-line comment: // This is a comment
✔ Multi-line comment:

/*
This is a multi-line comment
that spans multiple lines.
*/

Conclusion

JavaScript syntax defines the structure of writing code. By following proper syntax rules, developers can write clean, efficient, and error-free JavaScript code.

JAVASCRIPT

JavaScript Syntax

What is JavaScript Syntax?

Basic JavaScript Syntax Rules

1️⃣ JavaScript Statements

2️⃣ JavaScript Variables

3️⃣ JavaScript Data Types

4️⃣ JavaScript Operators

5️⃣ JavaScript Functions

6️⃣ JavaScript Conditional Statements

7️⃣ JavaScript Loops

8️⃣ JavaScript Comments

Conclusion