Every Paralympic sport has its own classification rules, designed to make sure that athletes and teams compete on equal terms.

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The rules are used to decide who is eligible to take part, and to group competitors in classes according to how much their impairment impacts on their performance.

The international body for each sport appoints officials – classifiers – to undertake the mammoth job of assessing each participant, something that takes place both before and during competition.

In some Paralympic sports, classification is relatively straightforward. For example in judo and powerlifting, competitors are divided only by weight. In goalball, the visually impaired and blind athletes wear blackout masks to ensure equality. In shooting, competitors are divided into mobility-dependent sub-categories within the main wheelchair and standing groups, while in sitting volleyball, a sixperson team can only have one player classed as Minimally Disabled (MD) on the court at a time - the rest must be classed Disabled. Other sports require a little more explanation, but all have a logical system and classification should not stand in the way of even a novice spectator’s enjoyment.