In computing, a process is the instance of a computer program that is
being executed by one or many threads. There are many different process
models, some of which are light weight, but almost all processes (even entire
virtual machines) are rooted in an operating system (OS) process which
comprises the program code, assigned system resources, physical and logical
access permissions, and data structures to initiate, control and coordinate
execution activity. Depending on the OS, a process may be made up of multiple
threads of execution that execute instructions concurrently.