Bullet hell (danmaku, lit. "bullet curtain") is a sub-genre of shoot 'em up video games in which the entire screen is often almost completely filled with enemy bullets. The genre is also occasionally known as curtain fire or as manic shooters. This style of game originated in the mid-1990s, and is an offshoot of Scrolling Shooters. Most of the well-known commercial games of this type are developed by the Japanese video game company Cave. The genre is also very popular in Dōjin Soft, particularly via the Touhou Series.