// JavaScript Timing Methods

// JavaScript provides built-in timing functions that allow you to

// delay or repeatedly execute code after a given time interval.

// These are asynchronous and handled by the browser’s Web APIs.

// The two main timing methods are:

// 1. setTimeout() → Runs a function once after a delay.

// 2. setInterval() → Runs a function repeatedly after each interval.

// setTimeout()

// Executes a function once after a specified delay (in milliseconds).

console.log("Hello world");

setTimeout(() => {

console.log("This message appears after 2 seconds!");

}, 2000);

console.log("End");

// Output:

// Hello world

// End

// This message appears after 2 seconds!

// Passing Arguments to setTimeout()

function greet(name) {

console.log(`Hello, ${name}!`);

}

setTimeout(greet, 1500, "David");

// After 1.5 seconds → Hello, David!

// Canceling a Timeout

// Use clearTimeout() to cancel a scheduled timeout.

const timeoutId = setTimeout(() => {

console.log("You will not see this message.");

}, 3000);

clearTimeout(timeoutId);

// Timeout canceled before execution.

// setInterval()

// Repeats a function continuously after a specified delay.

let count = 0;

const intervalId = setInterval(() => {

count++;

console.log(`Count: ${count}`);

if (count === 5) {

clearInterval(intervalId);

console.log("Interval stopped!");

}

}, 1000);

// Output:

// Count: 1

// Count: 2

// Count: 3

// Count: 4

// Count: 5

// Interval stopped!

// clearInterval()

// Stops an interval from repeating.

let number = 0;

const repeat = setInterval(() => {

console.log("Repeating task...");

number++;

if (number === 3) {

clearInterval(repeat);

console.log("Stopped repeating!");

}

}, 2000);

// setTimeout vs setInterval

// setTimeout() → Executes once after the specified delay.

// setInterval() → Executes repeatedly after each interval.

// Example: Using setTimeout() recursively (safer alternative to setInterval)

let counter = 0;

function repeatWithTimeout() {

counter++;

console.log(`Timeout Counter: ${counter}`);

if (counter < 3) {

setTimeout(repeatWithTimeout, 1500);

} else {

console.log("Finished repeating with setTimeout!");

}

}

repeatWithTimeout();

// Example: Simulating a Countdown

let countdown = 5;

const timer = setInterval(() => {

console.log(`Countdown: ${countdown}`);

countdown--;

if (countdown < 0) {

clearInterval(timer);

console.log("Launch!");

}

}, 1000);

// Summary

// setTimeout(fn, delay) → Executes a function once after delay.

// clearTimeout(id) → Cancels a timeout.

// setInterval(fn, delay) → Repeats a function every delay.

// clearInterval(id) → Stops a repeating interval.

// Both are asynchronous and managed by the browser’s event loop.