1. Promises: Promises are objects representing the eventual completion or failure of an asynchronous operation. They have two possible states: resolved (fulfilled) or rejected. Promises simplify asynchronous programming by allowing you to chain methods and handle success or failure with .then() and .catch(). 2. Async/Await: Async functions enable you to write promise-based asynchronous code as if it were synchronous. The async keyword before a function indicates that it will return a promise. Inside an async function, you can use the await keyword to pause execution until a promise settles (either resolves or rejects). Using async/await often results in cleaner and more readable code compared to using plain Promises, especially for handling multiple asynchronous operations sequentially.