PUBLIC MARKS with tags en.wikipedia.org & "explicação introdutória"

BulletML, or Bullet Markup Language, is an XML-based markup language used to define firing patterns of the enemies in 2D shoot 'em up games. It was created by Kenta Cho and is used in a variety of freeware games, such as the abstract shooters rRootage and Warning Forever.

A music video game, also commonly known as a music game, rhythm action game, or rhythm game, is a type of video game where the gameplay is oriented almost entirely around the player's ability to follow a musical beat and stay with the rhythm of the game's soundtrack. Since the game play for this type of game is largely aural rather than visual, this type of game is similar to audio games. However, music games generally require a visual component as well.