Skip to content
Skip to main content

About this free course

Download this course

Share this free course

Crossing the boundary: analogue universe, digital worlds
Crossing the boundary: analogue universe, digital worlds

Start this free course now. Just create an account and sign in. Enrol and complete the course for a free statement of participation or digital badge if available.

2.4.4 Manipulation

Suppose I take a digital photograph of myself for my website. Horrified by my wrinkled, baggy appearance, what can I do? Actually, with the right software I can do more or less anything I like: I can smooth out the wrinkles; I can restore the grey hair to its former splendour; I can even put in a background of books to give me a scholarly appearance. In fact, I can so improve the picture that if you met the real me you probably wouldn't recognise me.

‘Massaging’ my photographic image may seem a trivial reason for using a computer to acquire features of reality, but actually it has enormous significance. Figure 1 shows a landscape in which it may be difficult to distinguish what is real from what has been added by the computer. I say a bit more about this in Subsection 2.5.1, but a proper discussion will have to wait

Figure 1
Figure 1 A digitally manipulated image: half reality, half digital transformation, the illusion can be difficult to detect

Exercise 1

For each of the purposes above (storage, control, exchange, and manipulation), try to think of a specific example in which a computer is used for such a reason.


There is a huge range of examples you might have come up with. Here are just a few suggestions.

  • Storage and presentation

    • keeping copies of all your letters or digital films;

    • keeping records of all the books in a library.

  • Control

    • control programs in a washing machine;

    • traffic control systems in large towns.

  • Exchange

    • battlefield command and control systems;

    • exchange of data and command between ground control and distant space probes;

    • any computer network.

  • Manipulation

    • computer-aided design systems;

    • garden planning and design systems.