JavaScript Promises are a fundamental concept in asynchronous programming, allowing you to handle operations that may take time (like API calls or file reads) more cleanly. Here's a quick breakdown:

📌 What is a Promise?

A Promise is an object that represents the eventual completion (or failure) of an asynchronous operation. It has three states:

  • Pending: The default state, neither fulfilled nor rejected.
  • Fulfilled: The operation completed successfully.
  • Rejected: The operation failed.
JavaScript Promise Lifecycle

✅ Key Features

  • Chaining: Use .then() to chain multiple asynchronous operations.
  • Error Handling: Use .catch() to handle errors gracefully.
  • Parallel Execution: Use Promise.all() for concurrent tasks.
Promise Chaining Example

🧠 Use Cases

  • Fetching data from an API
  • Handling user input with delays
  • Managing file operations

📚 Learn More

For a deeper dive into promises, check our technical glossary or explore asynchronous programming tutorials.

Async/Await with Promises