This topic provides an introduction to MPI using a simple program. As you work on your own MPI programs, refer back to this material if you have questions concerning things like:

• In what order should MPI functions be called?
• What are the parameters, how are they ordered, and what do they mean?

The program itself is nothing more than the venerable Hello world! program, so we don't have to be concerned about understanding the purpose or the algorithm — rather, we can focus completely on the mechanics of accomplishing an extremely easy task in parallel.