The Revival is a race meeting that attempts (pretty successfully) to recreate the glory days of the Goodwood race circuit in the 50s and early 60s. It closed for racing in 1966 I believe. That's why there are plenty of period costumes etc. The Festival is a massive classic car event at Goodwood House complete with "hillclimb" up the drive that displays plenty of historic machinery in action. Both events are mega popular.