"Sometime in the future, Earth will be menaced by hordes of alien spacecraft that fly in predictable patterns and can be killed in one hit. The logical course of action will be to dispatch one brave hero in an untested plane/tank/spaceship to take them all on without help."A classic staple of The Golden Age of Video Games that has fallen out of favor in recent years. Everything is trying to kill you, and you have unlimited ammunition and a license to shoot first and ask questions later. Frequently, you're flying a spaceship or some other small craft, but other examples of the genre involve abstract shapes, people walking around with guns or bows and arrows, and so forth. So popular were shoot 'em ups (and their close-combat cousin the Beat 'em Up) that many computer games magazines of the mid-late 80s took to jokingly appending "'em up" to whatever genre of game they were reviewing — puzzle 'em ups, platform 'em ups, quiz 'em ups and so on. The term shmup is an abbreviation of "shoot 'em up", but is typically used by the fans who coined it to refer specifically to fixed-scrolling shooters that are not three-dimensional. For instance, 1943 would fit this description, whereas Geometry Wars would not (it is free-scrolling according to player movement), and neither would After Burner (it scrolls into/out of the screen in 3D). This kind of restrictive use is, however, debated among shoot 'em up fans. Power Ups typically increase the power and spread pattern of the primary weapon, which is usually fired continuously from the start of play until the end. Usually, a limited number of screen-clearing Smart Bombs are included to get the player out of a jam in a hurry. Many later games end their levels with a giant Boss Battle. The actual shooting part can vary in complexity. It can be as simple as holding down the fire button and never letting go or it can be more complex either due to ship's low firepower (e.g. Space Invaders) , scoring systems required to watch what and when to shoot (e.g. Radiant Silvergun) or other reasons. The Ur Example is quite possibly Spacewar! (although it's more of a one-on-one shooter rather than a shoot 'em up), the Trope Maker is Space Invaders, and the Trope Codifier is Galaga. Like a platform game, shoot 'em ups have become popular with amateur game developers for their relative ease of development. While very few professional examples of the genre have been developed recently — for example Gradius V, which wasn't developed by series creator Konaminote . The "Bullet Hell" sub-genre, characterized by very large numbers of slow-moving enemy projectiles has become relatively popular, along with the Lighter and Softer equivalent Cute 'em Up sub-genre with sometimes Moe aspects, although taken together they form an exception at present rather than the norm. Today, shoot 'em ups in general suffer from terminal It's Short, so It Sucks -itis from many critics. Worsening the decline is the redefinition of the term "shooter" — no longer used to refer to shoot-em-ups, they now refer to the distantly-related First-Person Shooter genre, or (merely) closer-related Third Person Shooter. Life In A Game spoofs them, specifically Star Fox, in Episode 4-2. Not to be confused with either the action film of the same name, or the other video game genre focused on shooting.
— Games Radar, "101 things we've learned from games"
Examples of this genre includes:Spacewar! derivatives: