The first person shooter genre is indisputably one of the most popular among PC gamers and has been for well over a decade. Whether it is for the technological leaps that a game has brought with it, the unseen interactivity for its time or just the plain fast-paced action that is fun to play, every couple of years there is at least one such great title that makes people drool incessantly until it’s finally out there for public consumption.

Yet, unfortunately with the staggering number of games that get released year after year, it’s not hard to miss the target and never come to play some of the best games this genre has to offer. Even some titles that have been critically acclaimed for some reason just don’t click with consumers and their fate inevitably leads to becoming one of those hidden gems of yesteryear, likely to never surface again.

We have come up with a list of 21 first person shooters that any serious FPS player shouldn’t have missed. The usual suspects obviously had to make it, but you're also sure to find some other oldies that you either didn't give a fair chance or just missed in the process. Simply put, we are going to take you on a stroll down FPS memory lane.

id Software
Wolfenstein 3D (1992)
It was the early 90s and a small development shop called id Software released a game for MS-DOS that would pioneer and popularize a genre that was barely taking shape. Wolfenstein 3D is to this day considered a landmark in the first person shooter genre for consolidating a style of gameplay that years later would evolve into other popular franchises of its own like Half-Life, Quake, Unreal and maybe even Doom itself.

Commonly also referred to as Wolf3D, the game is set in WWII and opens with the player taking control of an Allied spy captured by the Nazis and imprisoned after being caught spying on a top secret military project “Operation Eisenfaust” (“Operation Iron Fist”). After breaking free of your cell, you must find your way free of the prison and slaughter hundreds of Nazi soldiers in the process.

Wolfenstein today: Wolfenstein 3D has been ported to countless systems and has seen both a prequel and a sequel with another title currently under development by Raven Software (the development company behind Quake 4). There is no definite release date for the new Wolfenstein but it’s expected to be available for the PC, Xbox 360 and Playstation 3.

id Software
Doom (1993)
Doom wasn't quite the first FPS on the scene however it undoubtedly shaped the future of the genre, influencing countless other titles through the next 15 years and beyond.

Also developed by id Software, Doom furthered the technology previously seen in Wolfenstein adding different height levels in maps for the first time. The new game engine allowed for better graphics, lightning and character animations. Doom was also id’s first game that added network play, the multiplayer gaming mode later popularized as “Deathmatch”.

In Doom you played as a well armed space marine of sorts stationed on a Martian moon where all hell breaks loose after an extra-dimensional portal is opened and you're pit against a slew of demonic enemies. Whether it was the seemingly spooky music or the game's ability to throw a demon in your face at the right time, I'm not sure, but this title had me jumping out of my skin when I was a kid.

The Doom franchise today: As a follow up to the original title, Doom II as well as several other sequels and special editions based on similar technology have made their way into gaming history. A completely overhauled Doom 3 was released in 2004, though it failed to live up to expectations and had been considered by some to be more of a tech demo for its powerful engine than a full-blown FPS experience as Doom was in its time.

Looking Glass Studios
System Shock (1994)
System Shock managed to pull of something that no other title could in its time and it took several years until others followed up to its legacy. The game incorporated the finest elements of several popular genres in one neat little package.

Most easily described as an action packed first person shooter, System Shock blended in the feel of a role playing adventure game to provide the player with a unique experience that was unmatched in the mid-90s.

System Shock today: The original game had lackluster sales but in the years that followed it gained praise for the influence it had on later shooter titles. System Shock 2 was released in 1999 and was very well received, while a third sequel has been rumored for years now but nothing concrete has surfaced as of yet.

Also worth mentioning is that some years later the Deux Ex series had been strongly influenced by System Shock and it's not surprising given that Warren Spector was involved with the production of both games under separate studios.