Parallel computing has been a topic of interest in computing society over the previous few decades. Ever-growing amount of databases and increasing complexity of new problems are putting immense stress on the even the super fast modern single processor computers. Now the whole computer science society all over the world is looking for some computing environment where current computational capacity may be improved by a factor in order of thousands. The most understandable solution is introduction of multiple processors working in tandem that means the introduction of parallel computing.

Parallel computing is the simultaneous implementation of the same task, divided into subtasks, on multiple processors in order to get results faster. The idea is based on the fact that the process of solving a problem can generally be splitted in smaller tasks, which may be solved out all together with a number of coordination techniques. Before going into the particulars of parallel computing, we will discuss a number of basic concepts regularly used in parallel computing. Then we will elucidate why we need parallel computing and what the levels of parallel processing are. We will observe how flow of data takes place in parallel processing. We shall bring to a close this unit with a discussion of role the of parallel processing in a few fields such as engineering and science, database queries and the artificial intelligence.