PROMISE in js

A Promise in JavaScript is an object used to handle operations that take some time to complete, especially asynchronous operations.

A** Promise has three states:

Pending – operation is still running
Fulfilled – operation completed successfully
Rejected – operation failed**

Main Uses
Handling asynchronous operations
Promises are commonly used for tasks such as API requests, file operations, and timers.
Fetching data from APIs
The fetch() function returns a Promise.

fetch("https://example.com/data")
  .then(response => response.json())
  .then(data => console.log(data))
  .catch(error => console.log(error));

Avoiding callback hell
Promises make multiple asynchronous operations easier to organize than deeply nested callbacks.
Error handling
The .catch() method can handle errors in asynchronous operations.

myPromise
  .then(result => console.log(result))
  .catch(error => console.log(error));
`

Executing tasks in sequence
Promises can be chained using .then().

login()
  .then(getUser)
  .then(getProfile)
  .then(displayProfile)
  .catch(handleError);

Running multiple asynchronous tasks
Promise.all() can execute multiple Promises and wait for all of them.

Promise.all([task1(), task2(), task3()])
  .then(results => console.log(results));

Using async/await
Promises work together with async and await, making asynchronous code look more like normal sequential code

sync function getData() {
    const response = await fetch("https://example.com/data");
    const data = await response.json();
    console.log(data);
}