Interrupts are used to halt execution of a thread at predictable locations within your application code. Traditionally, the suspend and resume capability of a thread API would be used to interrupt the execution of a thread. But thread suspension is asynchronous and occurs regardless of the current activity of the thread. Suspending a thread that is currently holding a mutex can result in an unrecoverable deadlock situation. Even if your code does not explicitly use mutexes or other synchronization mechanisms, other libraries, such as a compiler’s run-time library, can use these mechanisms to protect global static data.

To avoid the problems associated with thread suspension, the Threading package can synchronously interrupt a thread executing within a runnable. This is done through the interrupt mechanism, rather than suspend and resume.