Classification is a crucial part of the Paralympics - without it, there would be no sport.
However, for the newcomer, it can be difficult to understand how athletes with different disabilities can compete against each other on a level playing field.
That's when Channel 4's groundbreaking Lexi Decoder will step in and break down the complexities of each sport for you.
Lexi will be used throughout the Paralympics on television and we also have a website which explains the classification process in all 20 sports: Lexi Decoder
You can find out more about the subject on the International Paralympic Committee's website.