Java applications execute via threads, which are an independent path of execution within a program. Any Java program has at least one thread, known as the main thread, which is created by Java Virtual Machine (JVM). Java is a multithreaded application that allows multiple thread execution at any particular time and these threads can run concurrently, either asynchronously or synchronously. When multiple threads are executing, each thread's path can differ from the other thread's paths.

The JVM provides each thread with its own stack to prevent threads from interfering with each other. Separate stacks help threads keep track of their next instructions to execute, which can differ from thread to thread. The stack also gives a thread its own copy of method parameters, local variables, and the return value.

Threads live within a process and share their...