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KotlinIntermediate4 min

Delay vs Thread.sleep?

Answer

Thread.sleep()

Blocking: Pauses the entire thread.
Cost: Expensive. The thread cannot do any other work.
Context: Java / Standard threads.

delay()

Suspending: Pauses the coroutine, not the thread.
Benefit: The thread is released to the pool and can execute other coroutines while waiting.
Context: Only available inside coroutines.

Always use `delay()` inside coroutines.

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