Working with diagrams
Working with diagrams

This free course is available to start right now. Review the full course description and key learning outcomes and create an account and enrol if you want a free statement of participation.

Free course

Working with diagrams

1 Seeing the world

1.1 Communicating information

With a heading like this one, you may be wondering if this course has suddenly turned into a travel brochure. If it had, would you carry on reading if there were no pictures of the places you could visit? I certainly wouldn't. I hesitate to use the old saying about ‘one picture saves a thousand words’, but if I didn't mention it you would be thinking it. Pictures or diagrams can be very evocative and thought-provoking, but they can also communicate a lot of information very quickly.

Activity 1

  1. Try to think of three examples of pictures or diagrams you see regularly in your home.

  2. Write down what these pictures or diagrams represent to you.

  3. What do you use them for?

(Here are some possibilities to get you started: newspapers, television, book covers, calendars, road maps, DIY books, washing-machine instructions.)


Here are my answers.

  • The first thing I had to hand was today's newspaper. It was full of photographs of things or events. I read a newspaper to tell me what is happening in the world, and it helps a lot to have pictures of people, places and happenings. I now know what my MP looks like. My rather hazy, abstract image has turned into a ‘real person’. I feel that I can now envisage how he might react in different situations. (When I'm reading a novel, I like to make up my own picture of what the characters look like.)

  • Next, I picked up a road map from the hall. This is a very colourful diagram that uses many types of symbols, but I find it easy to follow, using the key, and invaluable in planning my car journeys. It ‘represents’ how certain features of the real world relate to each other in terms of distance. So, for example, I know that the distance from Milton Keynes to Birmingham is about 110 kilometres, and that I can drive there in just over an hour.

  • The last diagram I noted was our calendar. This represents the days of the week – ‘time’ in other words – and enables me and my partner to make a note of important dates, such as my mother's birthday, our next dental appointment, and when my partner's next assignment is due in (and the fact that it clashes with a trip to the cinema). I can see at a glance all the things I feel I need to know, days, even weeks, in advance.

Here are some students' answers.

  • I wake up and look at my watch. There are 12 identical lines around the outside of a circular face. I know that these lines represent the hours of the day. The watch-face tells me that it is time to get up.

  • We have a gas cooker in the kitchen. There are six knobs with arrows on them. Each knob has a small picture above it. These pictures tell me that the grill is the second knob from the left, or that the small ring at the back is the knob farthest to the right, and so on.

  • My computing book tells me about aspects of my personal computer that affect how it runs and about how to improve its performance. I use the book for those reasons, but it's also helped by showing me what various bits of hardware look like. The label ‘hard drive’ was a grey area until I saw a picture of it. Suddenly, just by seeing that it was a cylinder of metal, I lost all the uncertainty that I used to feel when I read the words ‘hard drive’.

I can see a pattern in the examples I used in my answers. I started off with pictures of real-world objects or events in a newspaper. These pictures look very much like what my eyes would see if I were there, albeit only part of the full scene. Then I chose a road map, which is a very simplified diagram of what I would see if I were looking down from a plane. The map sets out to highlight certain things – such as roads, service stations and motorway junctions – that are relevant to car journeys. Yet, although this type of diagram shows things that are actually there for my eyes to see, it does not look at all like what my eyes would see. The red line on the map is obviously not actually a road – you can't drive on a red line. But we think of it as a road because we know that this is what the line stands for. The map is much easier to ‘read’ than an aerial photograph, because it leaves out a lot of detail that I don't need, and uses standard symbols to represent the things I do need to know about. Finally, I chose a diagram of something you can't actually see, although it represents something that you know exists – a continuing sequence of days that, for convenience, are grouped together in sevens as the days of the week.

There is similar variety in the examples chosen by the students. Some of them are pictures of real objects (for example, the hard drive in the computing book). Yet others (for example, the watch-face) represent interrelationships between things (lines) and concepts (time). And lastly, there are diagrams that act as convenient symbols to convey information (the symbols on the cooker).

Another impression I get from these examples is that they are all familiar. We all understand and use certain types and styles of diagrams from an early age: for example, reading the time from a watch-face. They are also an efficient way of organising information – for example, the calendar or the map. However, the types and uses of diagrams are rooted in cultural and/or different academic disciplines. So, a modern map looks quite different from an eighteenth-century map, and pictures of real objects are more common in biology (where things are easy to see) than in subatomic physics (where they are not so easy to see).


Take your learning further

Making the decision to study can be a big step, which is why you'll want a trusted University. The Open University has 50 years’ experience delivering flexible learning and 170,000 students are studying with us right now. Take a look at all Open University courses.

If you are new to university level study, find out more about the types of qualifications we offer, including our entry level Access courses and Certificates.

Not ready for University study then browse over 900 free courses on OpenLearn and sign up to our newsletter to hear about new free courses as they are released.

Every year, thousands of students decide to study with The Open University. With over 120 qualifications, we’ve got the right course for you.

Request an Open University prospectus