3.1 THE BASICS OF COMPUTERS COMPUTERS What is a computer? Virtually any device that works with a microprocessor can be called a “computer”. A is a digital electronic machine that can be programmed to store and process information at very high speed according to a set of instructions written in the binary system. computer Functions of a computer The five basic functions of a computer are: inserting data and instructions; processing; outputting or data or information; retrieving storing data; controlling devices and functions. Classification according to size Computers can be classified according to their size: are the biggest and fastest computers in terms of speed of processing data, are designed to process a huge amount of data, and are usually used in scientific and engineering applications such as weather forecasting and scientific simulations; Supercomputers are designed to support hundreds or thousands of users and multiple programs simultaneously; Mainframe computers are medium size and have two or more processors. They support up to 200 users at one time, and are used for , accounting, inventory management, etc.; Minicomputers billing are single-user computers designed for technical, business or scientific applications, and used to perform a single task with great accuracy; Workstations are generalpurpose computers designed for individual use . They are suitable for personal work and for entertainment, are small in size, and can support a limited amount of software. PC (personal computers) 1 MORE Laptops and desktops belong to this category. 1 Classification according to data handling capabilities Another type of classification is based on data handling capabilities: are designed to process data that changes continuously, so they are used in scientific and technological fields that continuously variable physical quantities such as electrical potential, fluid pressure, or mechanical motion; Analogue computers deal with can easily perform calculations and logical operations at high speed. All modern computers, like laptops, desktops and smartphones are digital; Digital computers are a combination of both analogue and digital computers. They are as fast as analogue computers with the memory and accuracy of digital ones, so they can process both continuous and discrete data. The electrocardiogram machine is an example of hybrid computer. Hybrid computers 2 MORE Discrete data is a finite value that can be counted, whereas continuous data has an infinite number of possible values. 2