PrintMultithreading is based on the notion of "threads" for a number of tasks that are executed within the same memory space. The advantage of this is that because the memory is shared between the threads they can share information. This results in a much lower memory overhead because information doesn’t need to be duplicated between threads. The basic logic is that a single thread starts off a task and then multiple threads are spawned to undertake sub-tasks. At the conclusion of those sub-tasks all of the results are joined back together again. Those threads might run across multiple processors or all on the same one depending on how the operating system (e.g. Windows) chooses to prioritize the resources of your computer. In the example of the PC above which has 4 processors, a single-threaded program would only run on one processor while a multi-threaded program would run across all of them (or as many as necessary).