Roguelike (or rogue-like) is a style of role-playing game traditionally characterized by a dungeon crawl through procedurally generated levels, turn-based gameplay, grid-based movement, and permanent death of the player character. Most roguelikes are based on a high fantasy narrative, reflecting the influence of tabletop role-playing games such as Dungeons & Dragons.

Though Beneath Apple Manor predates it, the 1980 game Rogue, an ASCII-based game that runs in a terminal or terminal emulator, is considered the forerunner and the namesake of the genre, with derivative games mirroring Rogue's character- or sprite-based graphics. These games were popularized among college students and computer programmers of the 1980s and 1990s, leading to hundreds of variants. Some of the better-known variants include Hack, NetHack, Ancient Domains of Mystery, Moria, Angband, Tales of Maj'Eyal, and Dungeon Crawl Stone Soup. The Japanese series of Mystery Dungeon games by Chunsoft, inspired by Rogue, also fall within the concept of roguelike games.

The exact definition of a roguelike game remains a point of debate in the video game community. A "Berlin Interpretation" drafted in 2008 defined a number of high- and low-value factors of "canon" roguelike games Rogue, NetHack and Angband, which have since been used to distinguish these roguelike games from edge cases like Diablo. Since then, with more powerful home computers and gaming systems and the rapid growth of indie video game development, several new "roguelikes" have appeared, with some but not all of these high-value factors, nominally the use of procedural generation and permadeath, while often incorporating other gameplay genres, thematic elements, and graphical styles; common examples of these include Spelunky, FTL: Faster Than Light, The Binding of Isaac, Slay the Spire, Crypt of the NecroDancer, and Hades. To distinguish these from traditional roguelikes, such games may be referred to as roguelite (or rogue-lite) or roguelike-like. Despite this alternative naming suggestion, these games are often referred to as roguelike and use the roguelike tag on various marketplaces such as Steam.

The term "roguelike" came from Usenet newsgroups around 1993, as this was the principal channel the players of roguelike games of that period were using to discuss these games, as well as what the developers used to announce new releases and even distribute the game's source code in some cases. With several individual groups for each game, it was suggested that with rising popularity of Rogue, Hack, Moria, and Angband, all of which shared common elements, that the groups be consolidated under an umbrella term to facilitate cross-game discussion. Debate among users of these groups ensued to try to find an encapsulating term that described the common elements, starting with rec.games.dungeon.*, but after three weeks of discussion, rec.games.roguelike.*, based on Rogue, which was at the time considered to be the oldest of these types of games, was picked as "the least of all available evils". By the time it was suggested that a group be created to discuss the development of these kind of games in 1998, the "roguelike" term was already established within the community. This usage parallels that of "Doom clone", a term used in the 1990s that later evolved into the more generic "first-person shooter".

Drawing from the concepts of tabletop role-playing games such as Dungeons & Dragons, nearly all roguelikes give the player control of a character, which they may customize by selecting a class, race, and gender, and adjusting attributes points and skills. At the start of the game, the character is placed at the top-most level of a dungeon, with basic equipment such as a simple weapon, armor, torches, and food. Following along the role-playing concept of a dungeon crawl, the player moves the character through the dungeon, collecting treasure which can include new weapons, armours, magical devices, potions, scrolls, food, and money, while having to fight monsters that roam the dungeon. Most combat is performed simply by attempting to move the character into the same space as the monster. The game then calculates the damage that the character and monster deal. Other types of attacks, such as firing an arrow or performing an offensive magic spell, can often be performed as well.

Defeating monsters earns the character experience points, and after earning enough points, the character will gain an experience level, improving their hit points, magic capability, and other attributes. Monsters may drop treasure to be looted. The character dies if they lose all their hit points. As most roguelikes feature the concept of permadeath, this represents the end of the game, and the player will need to restart the game with a newly made character. Roguelikes are nearly always turn-based, with the game only reacting when the player makes an action with the character. This allows players to evaluate a difficult situation, such as being cornered by several monsters, at their own pace and determine the best strategy.

The player generally has to explore the dungeon to reveal its contents, similar to a fog of war. Many roguelikes include visibility elements, such as a torch to provide illumination to see monsters in nearby squares, or line of sight to limit which monsters are visible from the player's position. Dungeons tend to be connected by stairs; lower dungeon levels generally are more difficult than higher ones, so that an underdeveloped character will have difficulty progressing too fast. Dungeon levels and the population of monsters and treasure within them are generated randomly using procedural generation, so no game is the same on subsequent playthroughs. Most roguelikes have an ultimate goal of either claiming an item located at the deepest level of the dungeon, or defeating a specific monster that lives on that level. Typical roguelikes assess the player's performance at the end of the game through a score based on the amount of treasure, money, experience earned, and how fast the player finished the game, if they managed to do so. The score is displayed in a ranked scoreboard to compare the player's performance on successive runs.

What gameplay elements explicitly define a "roguelike" game remains a point of debate within the video game community. There is broad agreement that roguelike games incorporate gameplay elements popularized by the text-based game Rogue (1980), which bore out many variations due to its success; As of 2015, several hundred games claiming to be roguelikes were available through the Steam game catalog, and the user-run wiki RogueBasin tracks hundreds of roguelikes and their development.