Difference between parallel computing,distributed computing and cluster computing?

Parallel Computing	Distributed Computing	Cluster Computing
-Many calculations are carried out simultaneously -Large problems can divided into smaller ones, which are solved concurrently in parallel	-Deals with hardware and software systems containing more than one processing element or storage element, concurrent processes, or multiple programs, running under controlled regime or by a network -Hightly scalable	-Working together closely and form a single computer -Mostly operate in shared memory mode -Tightly coupled with high-speed networking,mostly with optical fiber channels
Examples: Multi-core,Multiprocessor SMP,Massively Parallel Processing(MPP) Computers	-Telecommunication network -Network applications	Examples: HA,Load Balancing,Compute Clusters

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