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So what does this mean?
In the first place, computing is about achieving a piece of work, what the work consists of is irrelevant for the definition.
Grid computing is about achieving or completing a humongous piece of work which if given to a single computer would take an inordinately large amount of time and would also in all probability lock up the CPU cycles of the machine, leading to that notorious reaction ‘My computer froze”.
For people who are maybe not technically minded but are aware of SETI@home (The Search For Extra Terrestrial Intelligence – this is a volunteer computing project that utilizes the unused CPU cycles of volunteer home and work PCs to analyze radio signals emanating from space for signs of some sort of intelligent life out there. This seeks to answer that philosophical question “Are we the only ones out here on Planet Earth? It cannot be – there must be someone out there in the vast reaches of the universe”.
What this implies that each volunteer machine downloads a set of radio signal data, analyses it and sends the results back to the SETI project server. The SETI@home application is a screen-saver to be loaded onto the client machine.
This is what in technical terms is known as CPU scavenging and volunteer computing.