Chapter 2

The Computer

2.1 Computer systems are constantly developing, and manufacturers keep encouraging us to buy the latest, fastest systems, with the newest designs of keyboards, screens, more memory and faster processors, and so on. Give examples of circumstances in which having the latest technology is advantageous, and give examples when it can cause difficulties.


When raw computing power is at a premium, having the fastest computing power available is ideal - this is true for scientific applications, numerical modelling and analysis, and so on. Such increases in power can turn what were once batch jobs into interactive ones, allowing the user to explore and develop 'what if' scenarios that can lead to a better understanding of the underlying problems.

Developers of software usually benefit from having a faster design-code-compile-debug cycle, allowing them to produce their code more rapidly. However, this can cause problems too in that they become used to the capabilities of their machines and expect that all users will have similar resources. This can lead to large programs that perform ponderously on the more conventional machines that ordinary users have to work on.

2.2 Identify input and output devices that could benefit users with special needs.


Worked exercises

The following appear as worked exercises in Chapter 2:

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