Some people are 'near' or 'far' sighted. People who can see things up close but not far away are nearsighted, while people who can see far away things but not close-up things are farsighted. Either way, glasses or contact lenses help the person to see more clearly. But imagine if your eyesight was really poor. What would it be like if all you saw was a blur? Some people live with near-blindness or total blindness. What would you use to 'see' the world if you couldn't actually see using your eyes? Your other senses (hearing, smell, touch) would play a very important part. Try blindfolding yourself: naturally you use your hands to try and feel your way around!

We take it for granted that we can see in colour, but what if you only saw in black and white? How different would the world appear? What if you only saw one colour? Try looking through some coloured glasses and you'll see how different it is. Some people are colour-blind (this is more often found in boys than girls). This doesn't mean that the person can't see any colour, but usually means that they can't see certain colours like greens, reds and browns. This means that they see the world in colours that are very different to the way that you see them!