Inside Cisco IOS Software Architecture (CCIE Professional Development)

Operating Systems Basics

Modern operating systems provide two primary functions: hardware abstraction and resource management. Hardware abstraction gives software developers a common interface between their application programs and the computer's hardware so each individual programmer doesn't need to deal with the hardware's intricacies. Instead, the hardware-specific programming is developed once, in the operating system, and everyone shares.

The second function that operating systems provide is managing the computer's resources (CPU cycles, memory, and disk drive space, for example) so they can be shared efficiently among multiple applications. Like hardware abstraction, building resource management into the operating system keeps each application ...