Part 1 — Definition

A Promise is an object representing the eventual completion (or failure) of an asynchronous operation. It can be in one of three states: Pending, Fulfilled, or Rejected. This is much cleaner than "Callback Hell" (nested functions).

Part 2 — Syntax

const myPromise = new Promise((resolve, reject) => {
    if (success) resolve("Data!");
    else reject("Error");
});

myPromise.then(res => console.log(res));

Part 3 — Example

Problem: Simulate a data delay using setTimeout.

console.log("Start");
setTimeout(() => {
    console.log("Data loaded after 2 seconds");
}, 2000);
console.log("End");

Observation: "End" prints before the data message because JS is non-blocking.

Part 4 — Video

Video: Coming Soon

Part 1 — Definition

The Fetch API allows you to make network requests to get data from external servers. async/await is special syntax that makes asynchronous code look and behave like synchronous code, making it much easier to read and maintain.

Part 2 — Syntax

async function getData() {
    let response = await fetch(url);
    let data = await response.json();
    return data;
}

Part 3 — Example

Problem: Fetch a random user's information from a public API.

async function loadUser() {
    const response = await fetch('https://jsonplaceholder.typicode.com/users/1');
    const user = await response.json();
    console.log(`User: ${user.name} from ${user.company.name}`);
}
loadUser();

Part 4 — Video

Video: Coming Soon