| Shared (Global): There is a global memory space, accessible by all processors. Processors may also have some local memory. Algorithms may use global data structures efficiently. However "distributed memory" algorithms may still be important as memory is NUMA (Nonuniform access times) |
| Distributed (Local, Message-Passing): All memory is associated with processors. To retrieve information from another processors' memory a message must be sent there. Algorithms should use distributed data structures. |
