-- Java makes a distinction between a user thread and another type of thread known as a daemon thread. The daemon threads are typically used to perform services for user threads. The main() method of the application thread is a user thread. Threads created by a user thread are user thread. JVM doesn't terminates unless all the user thread terminate. You can explicitly specify a thread created by a user thread to be a daemon thread by calling setDaemon(true) on a Thread object. For example, the clock handler thread, the idle thread, the garbage collector thread, the screen updater thread, and the garbage collector thread are all daemon threads. A new created thread inherits the "daemon-status" of the thread that created it unless you explicitly calling setDaemon on that Thread object to change its status.
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