The Simple series is a line of budget-priced video games published by Japanese company D3 Publisher, a subsidiary of Bandai Namco Entertainment. Games in the series have been developed by several different companies, including Sandlot, Success, Irem, and Taito. It was introduced in 1998 for the PlayStation, and has been released for platforms such as the PlayStation 2, Nintendo DS, and mobile phones. The number in a series name indicates the price point of the games in the series; for instance, a "Simple 2000" series game would cost 2000 yen. Most of the games were developed specifically for the line, but it also included budget-priced re-releases of previously released games.