Real world musicians whose work appears in Class is a category for bands and individual musicians whose work appearing in a televised episode is not original to Class, but instead legally licensed or sampled by the Class production crew. Examples include Arctic Monkeys, The Temper Trap and Alex Clare.

Related to this category is:

• Real world musicians whose work appears in Doctor Who
• Real world musicians whose work appears in Torchwood

People in this category may be contrasted with:

• Doctor Who vocalists, who are people who performed original works for the production of Doctor Who, such as Katherine Jenkins or Mark Chambers.
• Performers of songs about the Doctor Who universe, people who have performed songs that never appeared in an episode, but which nevertheless had a strong Doctor Who connection. Examples: Jon Pertwee ("Who is the Doctor"), Orbital and their rendition of the Doctor Who theme, The Go-Go's ("I'm Gonna Spend My Christmas With A Dalek").
• Musical groups from the real world is an in-universe category, which organises musical groups who exist in the real world and the DWU. The Beatles are such a group.
• Musicians from the real world are individual musical performers who exist within the DWU. Frank Sinatra and Britney Spears are such people.