Maps and Compasses

A map is a picture of a place seen from above, like a bird flying high in the sky. Maps shrink the whole world down so it fits on a page. This view from directly above is sometimes called a bird's-eye view or a plan view. Learning to read a map is a brilliant skill that has helped explorers, sailors, and ordinary travellers find their way for thousands of years.

A compass works because the Earth itself behaves like a giant magnet. The needle of a compass is a small magnet that is gently pulled so that one end always swings to point towards the Earth's magnetic North. Once you know where North is, you automatically know all the other directions, because they never change their order around the circle.

Between the four main directions are the in-between directions: north-east, south-east, south-west, and north-west. Together with the main four, these make the eight points of the compass. Sailors and pilots use these to describe exactly which way they are heading, such as 'we are sailing south-west towards the harbour'.

Maps use a key (also called a legend) that explains what the symbols mean — a blue line for a river, a green patch for a forest, a tiny tree for a park. Symbols let a map show lots of information in a small space without writing words everywhere. Once you learn to read the key, you can understand a map of anywhere in the world, even if it is written in a language you do not speak.

Maps also use a scale, which tells you how much the real world has been shrunk. A scale might say that one centimetre on the map stands for one kilometre in real life. Without a scale you could not tell whether a map showed your back garden or a whole country! Many maps also have a grid of squares with letters and numbers so you can quickly find a place by its grid reference.