When WWE acquired World Championship Wrestling, WCW and Extreme Championship Wrestling, ECW in 2001, WWE decided the best way to deal with the influx of talent was to split the roster into two separate "brands" - RAW and SmackDown, named after their two signature shows, creating a "draft" the following year to see which wrestlers would henceforth be exclusive to a certain brand. Each brand would have their own pay-per-views that they would show up on, while both brands would appear on the "big four" pay-per-views - Royal Rumble, WrestleMania, SummerSlam, and Survivor Series. The calendar would be split up so each month would have one brand-exclusive pay-per-view event, necessitating more pay-per-view events being slowly integrated into WWE's event calendar. January's New Year's Revolution would be a RAW-exclusive event (alongside the dual-brand Royal Rumble. However, after WrestleMania 23 in 2007, it was announced that all future pay-per-view events would be inter-brand, returning to the way they were prior to the brand split (called a Brand Extension by WWE), resulting in the cancellation of New Year's Revolution, as well as all other pay-per-view events that were created solely for the purpose of furthering the brand extension.