◆ A cluster is a group of interconnected, whole computers working together
as a unified computing resource that can create the illusion of being one
machine.The term whole computer means a system that can run on its own,
apart from the cluster.
◆ A NUMA system is a shared-memory multiprocessor in which the access
time from a given processor to a word in memory varies with the location of
the memory word.
◆ A special-purpose type of parallel organization is the vector facility, which
is tailored to the processing of vectors or arrays of data.