A platformer is a video game genre where the player controls a character that is gravity-bound to platforms which he or she can walk along and jump or climb to other platforms. Traditional platformers are viewed from a side perspective, take place in a single screen, and require the player to maneuver from platform to platform while avoiding hazards. Although some game historians make jumping a requirement for the genre, I see this as arbitrary definition. Games like Space Panic and Crazy Climber, which were published in 1980, are among the first platformers, but the game to really bring the genre into the spotlight was Donkey Kong in 1981. It's popularity made sure the following year would be packed with platformers including Pitfall!, Popeye, Kangaroo, Donkey Kong Jr., and Miner 2049er. The quantity of platformers increased further in 1983 and continued to increase for another decade. The genre's core mechanic, walking along platforms, was quickly extended with scrolling backgrounds, and most new games in the genre adopted it as the standard.
As additional game mechanics were added into platformers, it became necessary to classify them in sub-genres. Mixing elements from the shooter genre resulted in the platform shooter, and evolving it further by making larger game worlds and power-ups created the Metroidvania. Later developers would combine sandbox elements, puzzle elements, Rouge-like elements, and pretty much everything else. Some genres incorporate the platform mechanic quite naturally because of their setting, like beat 'em ups. The platform genre reached its peak popularity in the mid-1990s, after which it was supplanted by the 3D platformer as new hardware made them possible. Although hardware now has moved well beyond what is necessary to make a humble platformer, the genre still remains a staple video game mechanic, and platformer games are still being developed to this day.
By the time I started playing video games, around 1985, the genre had already seen years of growth and hundreds of platformers existed across various sub-genres. However, despite the growing popularity of the genre, I rarely had access to new video games as my family had only an Atari 2600. At the time, my favorite traditional platformer was Pitfall!. I recognize the traditional single-screen platformer as a hugely important video game genre, I'm not a very big fan of it. To me, the games tend to lack depth, and it wasn't until the advent of increased memory and the smoothness of the scrolling platformer, and it's evolution to the Metroidvania, that the genre finally became interesting. The platform genre is one of my favorites, and it has strongly influenced my idea of how a video game should function.
This is a list of platformers that are important to me, for all platformers, see the category.