L02 OS Intro Part 1 Dr. Ken Hoganson
Chapter 1 Basic Concepts of Operating Systems
A computer system consists of two basic types of components: • Hardware components, which are the electronic devices and electromechanical devices, such as the processors, memory modules, disk units, keyboard, screen, and other devices. • Software components, such as the application programs, operating system, utilities, and other programs.
• The architecture of a computer system is the relationship among the various components. • Computer systems have the following three fundamental functions: processing, input, and output.
Structure of a Computer System
The basic structure of a computer normally consists of one or more of the following hardware components: • The CPU or the central processing unit, also called the processor • RAM or random access memory, also known as main memory • The massive storage devices, which store large amounts of data and programs in permanent form • The I/O devices or input/output units • The system bus, which provides interconnections for all components of the system
Hardware Structure of a Computer
• On a local area network (LAN), several small computers are connected to a larger computer called a server, and depending on the network topology, the smaller computers may also be connected to each other. • The server stores the global files or databases and may include one or more shared printers. • A much larger type of network is known as a wide area network (WAN) and covers a large geographical region and connects local area networks located in various remote places.
• An interrupt mechanism in which a hardware component (an I/O device) sends an interrupt request signal to the CPU. • This interrupt signal causes a temporary stop of the normal execution of a program, and the