In a Java program, each of the simultaneous tasks the computer handles is called a thread, and the overall process is called multithreading. Threading is useful in animation and many other programs.
Threads are a way to organize a program so that it does more than one thing at a time. Each task that must occur simultaneously is placed in its own thread, and this often is accomplished by implementing each task as a separate class.
Threads are represented by the Thread class and the Runnable interface, which are both part of the java.lang package of classes. Because they belong to this package, you don't have to use an import statement to make them available in your programs.
One of the simplest uses of the Thread class is to slow down ...