What is a Promise?

Node.js modules, files and async · Freshers

Model answer

A Promise represents a value that will be available later. It is pending, then fulfilled with a value or rejected with an error. You use .then() and .catch(), or await inside an async function. Promise.all runs several promises in parallel and waits for all.

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Async JavaScript in Node: Promises, async/await and the Event Loop in the course Node.js and Express: Build a Back End API from Scratch.

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