A string is a sequence of characters used to represent text. In JavaScript, strings are written inside single quotes (''), double quotes (""), or backticks (``) for template literals.

Creating Strings:

const name = "Alice";
const greeting = 'Hello';
const message = `Welcome, ${name}!`; // Template literal

Common String Methods:

• length – Returns the number of characters
• toUpperCase() – Converts to uppercase
• toLowerCase() – Converts to lowercase
• charAt(index) – Returns the character at a specific index
• includes(substring) – Checks if a substring exists
• indexOf(substring) – Returns the position of a substring
• replace(old, new) – Replaces part of the string
• slice(start, end) – Extracts part of a string
• trim() – Removes whitespace from both ends

Example:

const text = "  JavaScript is fun!  ";

console.log(text.length);           // 22
console.log(text.trim());           // "JavaScript is fun!"
console.log(text.toUpperCase());    // "  JAVASCRIPT IS FUN!  "
console.log(text.includes("fun"));  // true

Template Literals:

Use backticks ` and ${} to embed variables:

const name = "Bob";
const message = `Hello, ${name}!`;
console.log(message); // Output: Hello, Bob!

Tip:

Strings are one of the most used data types in JavaScript. Use string methods to clean, format, and manipulate text easily.

                        let str1 = 'Hello, world!';
                        let str2 = "Hello, world!";
                        let name = `John`;
                        console.log(str1, str2, name);  // Output: Hello, world! Hello, world! John
                                

                        let str = "Hello";
                        console.log(str.charAt(1));  // Output: e
                                

                        let name = "Alice";
                        let age = 25;
                        let greeting = `Hello, my name is ${name} and I am ${age} years old.`;
                        console.log(greeting);  // Output: Hello, my name is Alice and I am 25 years old.