You just keep going with the rest of the coat and then after 100 milliseconds, it'll just come back to this function and set time out is not the only form of asynchronous code in Java script that's built in the concept of promises, which is something that you see whenever you see a dot ben hur dot catch coming after a function, especially when you're doing fetching, for example, is another great example of asynchronous code that you don't actually know how long it's going to take.