Summary  
Promise.all aggregates multiple Promises into a single Promise that resolves with an array of all resolved values when every Promise succeeds or rejects immediately if any Promise fails.

General domain of usage  
Coordinating parallel asynchronous operations, such as sending multiple API requests concurrently.

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When you need to wait for several asynchronous operations to finish before continuing, `Promise.all` is the tool you use. You pass an array of Promises to `Promise.all`, and it returns a new Promise. This new Promise resolves only when every Promise in the array has been fulfilled. The resulting value is an array containing each Promise's resolved value, in the same order as the original array. If any of the Promises rejects, `Promise.all` immediately rejects with that error, and does not wait for the remaining Promises to finish. This behavior is helpful for handling multiple tasks that must all succeed before moving forward, but it also means that a single failure will stop the entire group.

What happens if one Promise in `Promise.all` rejects?

Master the core concepts of asynchronous programming in JavaScript, from the event loop to modern async/await syntax. Learn how JavaScript handles non-blocking operations, why asynchronous code is essential, and how to write robust, readable, and maintainable asynchronous code using Promises and async/await.

Explore why asynchronous programming is necessary in JavaScript, how it differs from synchronous code, and the mechanics of the event loop and callback queue.

Learn how Promises provide a cleaner, more manageable way to handle asynchronous operations, including creation, chaining, and combinator methods.

Discover how async/await syntax simplifies asynchronous code, making it more readable and maintainable.

Learn how to handle and debug asynchronous errors, avoid common pitfalls, and write predictable, non-blocking JavaScript code.

Using Promise.all

Using Promise.all