Explain async await to a simple brain

Async/await is a feature in Swift that helps manage asynchronous operations in a more readable and maintainable way. Here’s a simple explanation:

1. Asynchronous Operations: These are tasks that can take some time to complete, like reading from a disk or fetching data from a network. Instead of making your program wait and do nothing until these tasks are done, async/await allows your program to continue doing other work.

2. Async Functions: A function that can perform asynchronous operations is marked with the async keyword. This tells Swift that the function might need to pause and wait for some operations to complete.

3. Await Keyword: When you call an async function, you use the await keyword. This indicates that the function might pause at this point to wait for the asynchronous operation to finish. While it’s waiting, other tasks can use the CPU, making your program more efficient.

For example, if you have a function that fetches data from the internet, you would mark it as async and use await when calling it:

func fetchData() async -> Data {
    // Simulate a network call
    let data = await networkRequest()
    return data
}

When fetchData is called, it might pause at await networkRequest() until the network request is complete, allowing other parts of your program to run in the meantime.

For more details, you can refer to the session A Swift Tour: Explore Swift’s features and design which covers the basics of async/await in Swift.