|Fig: Operating System|
Operating systems are either single-tasking or multitasking. The more primitive single-tasking operating systems can run only one process at a time. For instance, when the computer is printing a document, it cannot start another process or respond to new commands until the printing is completed.
The below diagram gives a graphical depiction of the interfaces between the operating system and the computer component.
|Fig: Operating Systems Interfaces|
(Courtesy: www.contrib.andrew.cmu.edu, www.comptechdoc.org)