The coroutine builders bring together all of the components covered so far and actually launch the coroutines so that they start executing. For this purpose, Kotlin provides the following six builders:
•launch – Starts a coroutine without blocking the current thread and does not return a result to the caller. Use this builder when calling a suspend function from within a traditional function, and when the results of the coroutine do not need to be handled (sometimes referred to as “fire and forget” coroutines).
•async – Starts a coroutine and allows the caller to wait for a result using the await() function without blocking the current thread. Use async when you have multiple coroutines that need to run in parallel. The async builder can only be used from within another suspend function.
•withContext – Allows a coroutine to be launched in a different context from that used by the parent coroutine...