Analogue vs digital

For example, the turning of the wheel or changes in voltage can be used as input. Analogue computers are said to operate in real time and are used for research in design where many different shapes and speeds can be tried quickly. A computer model of a car suspension allows the designer to use the effects of changing size, stiffness and damping.

A typical analogue device is a clock in which the hands move continuously around the face. Such a click is capable of indicating every possible time of day. In contrast a typical clock is capable of representing only a finite number of times (every tenth of a second, for example_/ In general, humans experience the world analogically. Vision for example is an analogical because we perceive infinitely smooth gradations of shapes and colours. Most analogue events, however, can be stimulated digitally. Photographs in newspapers, for instance, consist of an array of dots that are either black or white. From afar, the viewer does not see the dots (the digital form), but only lines and shading, which appear to be continuous. Although Digital representations are approximations of analogue events, they are useful because they are easy to store and manipulate electronically.

When used in reference to data storage and transmission, analogue format is that in which information is transmitted by modulating a continuous transmission signal, such as amplifying a signal’s strength or varying its frequency to add or take away data. For example, telephones take sound vibrations and turn them into electrical vibrations of the same shape before they are transmitted over traditional telephone lines. Radio wave transmissions work in the same way. Computers, which handle data in digital form, require modems to turn signals from digital to analogue before transmitting those signals over communication lines such as telephone lines that carry only analogue format. The trick is in converting from analogue to digital, and back again.

This is the principle behind compact discs (CDs). The music itself exists in an analogue form, as waves in the air, but these sounds are then translated into a digital form that is encoded onto the disk. When you play a compact disc, the CD player reads the digital data, translates it back into its analogue form, and sends it to the amplifier and eventually the speakers.

The term digital describes any system based on discontinuous data or events. A digital device processes numerical information and pore generally manipulates symbolic information, according to specified computational procedures. The digital computer – embraces calculators, computer work stations, control computers (controllers) for applications such as domestic appliances and industrial processes, data processing systems, microcomputers, microcontrollers, multiprocessors, parallel computers, personal computers, network servers, and supercomputers.

A digital computer is an electronic computing machine that uses the binary digits. It can distinguish between just two values, 0 and 1, or on and off. There is no simple way to represent all the values in between, such as 0,25.All data that a computer processes must be encoded digitally, as a series of zeroes and ones. Every computer has a set of instructions that define the basic functions it can perform. Sequences of these instructions constitute machine-language programs that can be stored in a computer to tailor it to an essentially unlimited number of specialized applications. Calculators are small computers specialized for mathematical computations. General-purpose computers range from pocket size personal digital assistants (note-pd computers), to medium-sized computers (personal computers and workstations), to large powerful computers that are shared by many users via a computer network. Special-purpose microcontrollers are embedded, often visibly,, in devices like toys, consumer electronic equipment, and automobiles.

The main data processing elements of a computer reside in a small number of electronic integrated circuits (ICs) that form a microprocessor or central processing unit (CPUs). Electronic technology allows a basic instruction such as “add two numbers” to be executed many millions of times per second. Other electronic devices are used for program and data storage (memory circuits) and for communication with external devices and human users (input-output circuits) devices appear also to computers. They are used to construct input-output devices such as keyboards, monitors (video screens), secondary memories, printers, sensors, and mechanical actuators.

1. 
   A conventional clock (with hands) shows a more detailed time than a digital.
   
2. 
   An amplifier reads digital data.
   
3. 
   Demodulating happens when a signal is turned from digital to analogue.
   
4. 
   A modem helps to turn from digital to analogue.
   
5. 
   An analogue computer can be used by a car designer to test a new model.
   

1. 
   rigidity. Inflexibility (2^nd paragraph)
   
2. 
   any method of dispersing energy in a vibrating system (2^nd paragraph)
   
3. 
   having a countable number of elements (3^rd paragraph)
   
4. 
   recognize or observe (3^rd paragraph)
   
5. 
   a series of systematic changes (3^rd paragraph
   

VOCABULARY