The message passing model is usually applied in cases where each processor has its own memory (distributed memory system). More tasks can reside on the same physical machine or on an arbitrary number of machines. The coder is responsible for determining the parallelism and data exchange that occurs through the messages, and it is necessary to request and call a library of functions within the code.

Some of the examples have been around since the 1980s, but only in the mid-1990s was a standardized model created, leading to a de facto standard called a Message Passing Interface (MPI).

The MPI model is clearly designed with distributed memory, but being models of parallel programming, a multiplatform model can also be used with a shared memory machine: