Thread.sleep() in Java with Examples

Thread.sleep() is part of Java concurrency. A thread is a path of work inside a process. Create with Thread or Runnable, then call start() — not run(). run() only runs on the same thread.

For Thread.sleep(): if two threads share data, synchronize or the result can be wrong. sleep pauses. join waits for another thread to finish. daemon threads die when all user threads finish.

Thread.sleep() deadlock: two threads wait for each other’s lock forever. Avoid by locking in the same order. Don’t guess thread order — it can change every run.

Let's take this on the board with one tiny Main class — no extra files. Thread.sleep() in Java with Examples — sleep pauses the current thread for ~200ms. Start from main, go line by line, and stop at each print. That output is the proof for Thread.sleep().