This is an introduction to rhythm simulation as a genre to help players understand the game better, and perhaps enable greater appreciation by being more informed.

What is a rhythm game? Rhythm games, also sometimes known as music games utilize music as a strong concept or theme in its mechanics, often times challenging the player's sense of rhythm and timing. For the purposes of this guide, rhythm games will be classified into two main categories. The first type is called rhythm simulation. Any rhythm games that engage the player in choreographed actions with a song through some means is considered to be of this type. The mechanics and types of actions the player must do are usually meant to give the player the feeling like they are "playing" the music, or "become one with" the music. Examples include Etterna, Osu, DDR, Guitar Hero, Pop'n Music, Technika, and IIDX. Most of the games of this type are also known as VSRG's, or Vertical Scrolling Rhythm Games, because they involve notes flying vertically towards a receptor. All other rhythm games fall under the second type. These rhythm games generally don't follow the emulation aspect of rhythm simulation, but use their own means of portraying or relating music through some mechanic. Examples include Bit Trip Beat, The Polynomial, Chime, and Turba. Rhythm games, like any other games, can be a combination of different game genres, and so this categorization is only intended to be a crude conceptual generalization. Some games could arguably be considered either type.

The bulk of this library will be referencing a particular rhythm simulation game as its focus, which we will call KeyBeat or KBO to distinguish the particular playstyle mechanics to its own game and avoid confusion. However, keep in mind that there are many similarities between the described game and most VSRG's in general. Few games are more straightforward than KBO in terms of concept. Notes fly toward a receptor and are hit in time when they intersect, similar to many other VSRGs. Unlike other some rhythm games that have a specific theme, such as Guitar Hero and its focus on rock music, KeyBeat does not have a specific theme. The buttons you use to play are not associated with any instrument, object, or concept. The purpose of this is to create a more universal rhythm game that will appeal to all audiences as well as provide variety and replayability from custom community-created levels. Because of this kind of universality and the fact that the community has made many thousands of levels over the course of many years, KeyBeat allows for a lot more possibilities in the number of ways the notes can line up with the music, resulting in a game with a lot more variety and creativity than specialized commercial rhythm games, in which the level and game design follows certain design standards in technicality (and inadvertently, style) to a greater degree. In addition, this guide will particularly focus on the two playstyles 4k and 6k, which stand for "4 key" and "6 key" respectively, indicating the number of buttons, and thus the number of receptors and columns.

Although KeyBeat, like any other game, is an activity that is ultimately played for enjoyment or competition, it goes further than being just that. Rhythm simulation aims to capture and celebrate the way we perceive music and enhance it, expand it, and challenge it. KBO highlights the essence of the rhythm simulation genre, presenting a large range of creative works in a more universal medium. Often times, this game introduces people to new genres and styles of music they wouldn't have discovered otherwise. When you play rhythm simulation games, try to be more open-minded about the types of levels and range of songs that you play. For much of the community, these games are how players have expanded their tastes in music, allowing them greater appreciation of not only the game genre, but music in general!