Unlike Java or Python, Javascript does not have a built-in sleep function. So, how might you be able to implement a method with the same functionality as the [sleep function](https://www.educative.io/answers/what-is-the-sleep-function-in-python)?

A simple way to create a delay in Javascript is to use the `setTimeout` method. The example below would log `Hello`, wait two seconds, and then log `World`. For many, this might be enough to do the trick.

console.log("Hello");
setTimeout(() => {  console.log("World!"); }, 2000);

Still, the noticeable drawback is that `setTimeout` is an asynchronous method, meaning that the code below will log `Hello`, `Goodbye!`, and then, `World!`. This could be a problem for some of your programs if you want the program to print in the order `Hello`, `World!`, and `Goodbye!`.

console.log("Hello");
setTimeout(() => { console.log("World!"); }, 2000);
console.log("Goodbye!");


function sleep(ms) {
  return new Promise(resolve => setTimeout(resolve, ms));
}

async function delayedGreeting() {
  console.log("Hello");
  await sleep(2000);
  console.log("World!");
  await sleep(2000);
  console.log("Goodbye!");
}

delayedGreeting();

The `sleep` function above utilizes the `setTimeout` function to resolve a `Promise` after a specified number of milliseconds. 

The asynchronous function allows us to return a `Promise`, and we use `await` to get the return value. With this, we can utilize the `sleep` method in the function to set up a delay. 

**Some things to know:**

- The method does not pause the entire program, only the `async` function

- `await` only pauses the current `async` function

- The ES6 feature `Promise` allows us to design this sleep function

What is the Javascript alternative to the sleep function? 

Use the setTimeout method or an async sleep function with Promises for delays in JavaScript.