There are now five main categories. These are the amputuee category (anyone who has needed to have a limb removed); the cerebral palsy category; the visually impaired category, which includes complete blindness; the spinal injuries or other disabilities category; and the intellectual disabilities category. The last category was only just added in time for the 2012 Games, but the first British gold medal has already been awarded to a swimmer in that category.

In the past there was a further category of 'other' for anyone who didn't fit the others, but it was eventually decided that all participants could fit one of the other four classes.

There have been discussions about other categories too. For example, a hearing impaired category was proposed in the past but decided against.

Within the categories, athletes are further divided into classes, based mainly on type and degree of disability. You can learn more about the way this is done if you go online to the London 2012 Guide to the Paralympic Games.