Grid+computing,+distributed+processing

**__Grid Computing__**

Grid computing is a form of distributed computing. Thought not about sharing files, distributed computing focuses on sharing processing power. One type of grid computing, sometimes called **//volunteer computing//**, involves creating a virtual network of geographically dispersed computers to work on a problem that's too big to solve with a single machine or LAN. The best-known example is SETI@Home (setiathome.ssl.berkeley.edu), a program that puts PCs all over the internet together into a virtual supercomputer that analyses space telescope data in the search for extraterrestrial life.

Another form of grid computing, sometimes also called //**utility computing**//, involves offering computational power and storage as metered commercial services, with the Internet acting like a utility grid. Grid-computing applications are currently being used by the U.S. Department of Defence, the U.S. Department of Energy, NASA, the UK National Grid, and a variety of academic and scientific communities. The ultimate in grid computing is a grid that spans the internet.



= __Distributed Processing__  = Distributed processing is a phrase used to refer to a variety of computer systems that use more than one computer (or processor) to run an application. This includes **//parallel processing//** in which a single computer uses more than one CPU to execute programs.More often, however, distributed processing refers to local-area networks (LANs) designed so that a single program can run simultaneously at various sites. Most distributed processing systems contain sophisticated software that detects idle CPUs on the network and parcels out programs to utilize them.Another form of distributed processing involves distributed databases. This is databases in which the data is stored across two or more computer systems. The database system keeps track of where the data is so that the distributed nature of the database is not apparent to users.