What is the difference between using Promise and async/await syntax?

Promise is an object that reflects the eventual completion or failure of an asynchronous operation. It manages asynchronous flows using callbacks .then() and .catch().

async/await is syntactic sugar over Promise, making asynchronous code more readable and similar to synchronous code. A function marked as async always returns a Promise. The await operator can only be used inside an async function and it pauses the execution of the function until the Promise is fulfilled or rejected, then returns its result or throws an exception.

Aspect	Promise	Async/Await
Readability	Requires chains of .then() and .catch()	Looks like synchronous, linear flow
Error handling	Uses .catch()	Uses try...catch blocks
Execution flow	Managed by callbacks	Pauses/resumes the function
Return value	Promise	Promise (for async functions) or Promise result (for await)
Dependency	Standalone mechanism	Built on Promise

Example with Promise:

// Promise example
function fetchDataPromise() {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve("Data received (Promise)");
    }, 1000);
  });
}

fetchDataPromise()
  .then(data => console.log(data))
  .catch(error => console.error(error));

Example with async/await:

// async/await example
function fetchDataAsync() {
  return new Promise((resolve, reject) => {
    setTimeout(() => {
      resolve("Data received (async/await)");
    }, 1000);
  });
}

async function showData() {
  try {
    const data = await fetchDataAsync();
    console.log(data);
  } catch (error) {
    console.error(error);
  }
}

showData();