The reason we want to take a look at a background thread specifically is because, by default, all threads created by the main app thread or Thread class constructor are foreground threads. So, what exactly separates a foreground thread from a background thread? Well, background threads are identical to foreground threads with the exception that if all foreground threads are terminated, the background threads are stopped too. This is useful if you have a process in your application that must not stop the application from terminating. In other words, while your application is running, the background threads must continue to run.