Introducing Computer Systems

Computer - A computer is an electronic device that processes data, converting it into information that is useful to people.

Computers can be categorized in several ways. For example, some computers are designed for use by one person, some are meant to be used by groups of people, and some are not used by people at all. They also can be categorized by their power, which means the speed at which they operate and the types of tasks they can handle. Within a single category, computers may be sub-categorized by price, the types of hardware they contain, the kinds of software they can run, and so on.

Personal Computers - A term that refers to any computer system that is designed for use by a single person.

Desktop Computer - The most common type of personal computer, designed to sit on (or under) a desk or table.

System Unit - The main component of a desktop PC, the case that houses the computer's critical parts, such as its processing and storage devices.

Workstation - A specialized, single-user computer that typically has more power and features than a standard desktop PC. These machines are popular among scientists, engineers, and animators who need a system with greater than average speed and the power to perform sophisticated tasks.

Notebook Computers - Or laptop computers, weigh less than 8 pounds and run on special batteries.

Tablet PC - Offer all the functionality of a notebook PC, but they are lighter and can accept input from a special pen called a stylus or a digital pen that is used to tap or write directly on the screen.

Handheld PC - Handheld personal computers are computing devices small enough to fit in your hand. A popular type of handheld computer is the personal digital assistant (PDA).

Smart Phones - A phone that doubles as a miniature PC. These phones offer advanced features not typically found in cellular phones, like internet access or email.



Network Servers, Mainframes, Minicomputers, and Supercomputers - are commonly used by organizations and support the computing needs of many users.

Network Server - is a powerful personal computer that is used as the central computer in an organization's network. In many companies, workers use their desktop systems to access a central shared computer.

Mainframes - are powerful, special-purpose computers that can support the needs of hundreds or thousands of users.

Minicomputers - support dozens or hundreds of users at one time.

Supercomputers - are the largest and most powerful computers made.