sleep(long ms) - causes the thread to sleep for the specified number of milliseconds.
yield() - provides a hint to the scheduler that this doesn't have to run at the current time, so the scheduler can choose another thread to run if need be.
join() - used to let one thread wait for another to terminate.
interrupt() - used to request that the thread cancel itself.
notifyAll() - wakes up all waiting threads.
wait() - used to pause the thread, presumably while it waits for some condition to be satisfied.
