Introducing maps

Map and compass

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Data run

Facts might be sacred, but their value lies in their interpretation. Introducing data.

An article about making and understanding maps, from the BBC/OU series Coast

A map on its own is meaningless (try showing one to a person from a culture which does not include mapmaking as we know it). A map is neither a picture nor a story – unless we know how to “read” it. Critical awareness is vital in recognising how mapmaking involves selecting, distorting and generalising just as with text, photographs and statistics.

None of these issues is necessarily a problem, so long as you know about them. Maps, then, are an abstraction involving science and technology, imagination and skill and, above all, decisions. So, to bring a map alive, we need to know about the codes and conventions that lie behind its production. We also need to understand both the obvious messages and the underlying, often hidden, meanings.

Fundamental to producing a map is the relationship between data (the information you wish to display and convey) and space, both the geographic space being represented and the space available on the sheet of paper. Data is represented by:

points (to show location)
lines (to show connections)
symbols (to convey features); and
colour and/or shading (to represent areas).

These are the codes which are part of the language of maps.

The other side of that basic relationship between data and space is the classic problem of representing a spheroidal earth (or, globe) on a plane surface. The resulting “projections” are often controversial. There are also conventions which are observed in mapmaking. Look at the map below which highlights the main conventions.

Map with title, scale, orientation, gridlines, centre, projection, source, date and key

Aspects to consider in the process of reading maps

Some of the features on the diagram may be obvious. However, other conventions, like “projections”, may need some further reading. Our diagram does not mention the use of colour and our illustrations in this text are in black, white and shades of grey. Colour can play a major role in conveying messages on a map, for example; it may convey political, diplomatic features as well as geographical ones.