Parallel processing: The operating system that is used to operate, control and manage a parallel computer system is called parallel processing operating system. Any system that has more than one CPU can perform parallel processing, as well as multi-core processors which are commonly found on computers today. Multi-core processors are IC chips that contain two or more processors for better performance, parallel processing is commonly used to perform complex tasks and computations. The parallel execution can be achieved by executing multiple processes on different processors in parallel. In parallel processing operating system the task of a program that required many calculations is divided into many smaller tasks and these are processed by multiple processors at the same time Distributed Operating system Book: A distributed operating system is an operating system that manage a group of indepen...