Shark Week is an annual, weeklong, shark-themed TV programming block at the Discovery Channel. Shark Week originally premiered on July 17, 1988. Featured annually, in July or early August, it was originally devoted to conservation efforts and correcting misconceptions about sharks. Over time, it grew in popularity and became a hit on the Discovery Channel. Since 2010, it has been the longest-running cable television programming event in history. Broadcast in over 72 countries, Shark Week is promoted heavily via social networks like Facebook and Twitter. Episodes are also available for purchase on services like Google Play Movies & TV/YouTube, Amazon Video, and iTunes. Some episodes are free on the subscription-based Hulu and Discovery+.