Minesweeper, FreeCell, and Spider Solitaire. The company published four Microsoft Entertainment Packs for casual gaming on office computers from 1990 to 1992. Casual games started to flourish online in the 1990s along with the rise of the World Wide Web, with card games and board games available from paid services like AOL and Prodigy, and then from web portals, like Yahoo! Games and Microsoft's Gaming Zone. In the mid-2000s, more sites specialized in game hosting and publishing, such as Gamesville and RealNetworks. Some publishers and developers branded themselves specifically as casual game companies, like Big Fish Games, PopCap Games, and MumboJumbo. The advent of Shockwave and Flash created a boom in web-based games, encouraging designers to create simple games that could be hosted on many different websites and which could be played to completion in one short sitting. One of the most prominent casual games, Bejeweled, started out as a Flash game that could be downloaded for a fee, or purchased at retail. As late as 2009, there was still a market for US$20 casual games purchased at retail or as a download. In 2008 and 2009, casual social network games rapidly attained mainstream popularity following the release of Mafia Wars for Facebook, and Happy Farm in China. Happy Farm inspired many clones, including the most popular social network game, FarmVille (2009), which peaked at 83.76 million monthly active users in March 2010. These games innovated in viral marketing by rewarding players for sending invites to friends and posting game updates on their Facebook Wall. Casual games became popular on smartphones immediately upon their debut, with touch-screen phones like the iPhone of 2007 featuring large color displays, all-day availability to the phone owner, and intuitive tapping-and-dragging user interfaces. Video game consoles' primary audience is hardcore gamers, but there are some casual games on every game console, and Nintendo's Wii console's unique motion-sensing controller appealed to a more casual audience that was perhaps intimidated by other consoles' gamepad input devices. Wii Sports (2006), a collection of five simple sports games in which players used the game controller to swing a tennis racket or a baseball bat, was bundled with the Wii console in most territories and sold over 82 million copies as of 2019. Genres Casual games are found in many game genres. Early-2000s categorizations by Big Fish Games and Gamezebo, a casual game review site named seven popular genres in