For my entire life, I have been fascinated by video game controllers. When I see a controller I've never used before, even if it's not plugged into anything, I need to pick it up and play around with it. I have always felt that the way a game controls is one of the most important aspects of game design, if not the most important. In most games, it is desirable for the interactive elements to be responsive, intuitive and satisfying. Using the input method available to provide the best experience to the player is important, and the best input devices for games take the gameplay experience into account.
Early on, game controllers were designed around specific games. The monstrous Telstar Arcade (pictured above) features Pong-style paddles, a steering wheel and a gun. Soon enough, action games really caught on in the arcades, and the traditional joysticks and buttons of arcade cabinets became the norm. The earliest notably successful console, the Atari 2600, attempted to emulate the arcade experience as best it could. The standard 1-button-and-joystick controller couldn't quite hold up to the arcade experience, but it tried. This type of controller, with various improvements and variations, was generally the standard console game input for the next few years. It wasn't until the Nintendo Entertainment System that the game controller as we know it today was truly born.
Meanwhile, PC gaming was finding its footing. The keyboard as an input device has continued to see prominent use to this day, with very little variation. A device with around 100 buttons, especially one that many users are already familiar with, is incredibly versatile and can be used for a wide variety of play styles. Despite the universal nature of the keyboard, a handheld controller has its own advantages. It's small, it's simple, you can pass it to your friends. Many NES games didn't even really need to teach the user how to play. You only have so many options, so it made sense to just try all of them. A PC game can't really be designed this way, at least not without assuming users are familiar with genre conventions. The biggest disadvantage that a keyboard, and even a mouse and keyboard, have compared to a controller is that they are not made for games. They do work best for certain genres that originated and continue to thrive on PC, though. These genres, such as real time strategy games, first person shooters and western role playing games, are built around mouse and keyboard input. They have had a presence on consoles, but by most accounts do not control quite as well. Even amid the massive success of Halo and the console versions of Call of Duty, many gamers refuse to play first person shooters on any platform other than PC.
But there is a difference between PC input devices, as well as mobile phone inputs and other multi-purpose devices, and a controller. A controller is meant for games, and is designed around games. The NES controller, despite introducing some universal conventions, does not really do anything that keyboards couldn't do. But the form factor is specifically designed around games. In the post-market crash world of console games, inspiration was drawn heavily from the NES controller. Sega was the first notable competitor to borrow from Nintendo, with the Sega Master System's controller having a practically-identical form factor.
By the early 90s, it was clear that all of Nintendo's competitors were playing catch up. NEC's TurboGrafx 16 only had 2 main buttons. The Sega Genesis added a "C" button in addition to "A" and "B", giving it 3 main inputs instead of the 2 buttons of the NES. Then the Super NES added 4 more buttons, including shoulder buttons.
The difference here is that Sega seems to have been making an attempt to get the leg up on Nintendo with the Genesis. They were attempting to do what "Nintendon't", and maybe bring users closer to the arcade experience. The SNES, on the other hand, was arguable the first console controller to really attempt to bring something different to the table. It was clearly not emulating the arcade experience. Though functional for arcade ports, the idea of putting 6 buttons within easy reach made faithful ports of games like Street Fighter II very possible, the true strength of the SNES controller was what it brought to console-specific games.
The now-traditional diamond button format was unusual in 1991. This not only puts 4 face buttons within easy reach of each other, but also allows users to mentally arrange buttons better than they might with a row of buttons. The Sega Genesis later had a controller with 6 face buttons, as did the Sega Saturn, and while this setup works great for certain genres and is loved by many, the fact that it requires longer movements and different resting positions can lead to some level of player confusion. The SNES tends to not have this problem, and allows the user to forget about the controller and just enjoy the game. This type of control method cannot really be matched using a mouse and keyboard, and has allowed console games to evolve in a divergent direction. That said, the most notable innovation of the SNES controller was certainly the shoulder buttons. Shoulder buttons were very likely added to the SNES controller to account for the new "mode 7" graphical effect, allowing better control of direction during pseudo-3D segments. Sony and Sega used similar logic for including shoulder buttons on the PlayStation and Saturn (respectively), with Sony taking it a step further by including 4 shoulder buttons.
The introduction of 3D console games threw a wrench into the idea of the NES-inspired console controller. This was one of the most diverse console generations in terms of controller design. Sony's PlayStation controller was clearly inspired by the SNES controller, but the extra row of shoulder buttons did have a permanent impact on controller design and game design. Although they never really caught on in terms of 3D control, they did offer more options to the fingertips of users. Diverging farther and farther from PC and arcade games, the PlayStation's controller was made for console games.
Meanwhile, the Sega Saturn failed to be forward-looking in several ways. Sega was smart to fully embrace the CD, even if they were maybe a little bit early to the party, but they made the mistake of initially designing their console around being a strong 2D box. The 3D graphical capabilities of the Saturn suffered as a result, but taking it a step further, the controller was just not made for 3D. Shoulder buttons were added, but the 6-button layout of the controller's face was still clearly tailored to ports of arcade games. These types of games certainly had a market, especially in the 90's, and to this day the Saturn controller is regarded as one of the best controllers ever made. But it was not forward looking. It was not tailored toward the direction console games were headed, and it didn't really accommodate 3D games in any specific way. Shoulder buttons were added, but at this point that was the bare minimum.
With an analog stick present from day one, the Nintendo 64 embraced 3D games. Nintendo may not have embraced CD technology, and the N64 controller was not perfect (with a completely separate d-pad available almost as a safety net in case the 3D experiment didn't work), but Nintendo were incredibly forward looking in terms of game design. They went all-in with 3D games, and the Nintendo 64 controller was a key component of this new direction. Super Mario 64 was a revolution, and it absolutely would not have been possible with any other controller at the time. A keyboard and mouse couldn't pull it off. The PlayStation couldn't either, nor could the Saturn, the 3DO or the Jaguar (although they had a wealth of other problems that lead to a lack of success, it is interesting to note that the Jaguar and 3DO are both known for having terrible controllers).
The Saturn got an analog controller, the PlayStation got an analog controller. PC games got analog controllers. Sony's analog controller is notable for adding a second joystick, which has since become the industry standard. In fact, the modern idea of the controller is essentially the PlayStation's DualShock controller. It became such a standard, that the Dreamcast and GameCube suffered from having fewer buttons. Dreamcast, as cool as many of the games on the console were, did suffer quite a lot from having a limited controller. Although I wouldn't necessarily say the controller contributed to its demise, it would have been extremely hard for it to compete with the PS2, Xbox and GC with a dramatically lower number of buttons. While the GameCube controller is fantastically comfortable and works very well with Nintendo's own games, it is not nearly as utilitarian as the Dual Shock or even the original Xbox controller. When Sony attempted to reinvent the DualShock for the PlayStation 3, the backlash was so harsh that they reverted back to the old design (though to be fair, Sony in 2006 wasn't exactly hitting anything out of the park).
It was during the PS2's generation that the DualShock really established itself as the "standard". Microsoft did a great job of emulating (and, in the opinion of many people, improving upon) the universal nature of Sony's controller with their Xbox 360 controller, and even Nintendo in their post-Wii afterglow decided to embrace this type of controller with the Wii U. The simple fact now is that many console games assume there are 4 shoulder buttons, 4 face buttons and 2 analog sticks (that you can also push as buttons). To do anything else means less third party support, or ports that suffer from a lack of inputs (as seen on the GameCube). It has been interesting to see the idea of a controller go through iterations before settling on what many see as the "right" way to control most games (with genre-specific exceptions - such as arcade sticks for fighting games and instrument controllers for music games).
Emulating the DualShock is not the only option, though. The original Wii was an inventive reaction to the market's rejection of the GameCube. Nintendo decided not to compete on power, and instead introduced a new input method. In a way, this has always been what Nintendo has done. Input devices have been a huge part of the appeal of Nintendo consoles, and with the Wii's motion controls they appealed to an all new market. Games had to be built to function around this device, and allowed the Wii to introduce a number of new gameplay experiences.
Although I love the Wii U gamepad, I am a little bit disappointed that Nintendo didn't go all-in with motion controls. I can get traditional controller experiences elsewhere, and even though having a screen is nice, it does not fundamentally change gameplay. The Wii remote has its problems, but when it works well it provides something not found anywhere else. Even on the Wii U, Pikmin 3 controls best with Wii-style controls.
Nintendo's promotional images like this are one of the best things about the Wii.
The PS4 and Xbox One offer interesting evolutions of their predecessors' controllers. Both have ditched pressure-sensitive buttons (a standard feature for the past two generations that was barely utilized), both have improved their directional pads (surely a reaction to the resurgence of fighting games and 2D platformers), and both have made attempts to tailor their analog sticks and triggers better towards shooters. Sony also chose to add a touch pad and take further steps to integrate motion controls into the controller (something they began with the PS3's "SIXAXIS" functionality), which could be seen as reactions to the mobile gaming and motion gaming. It is clear that the designs of past games, and a forecast of where game design is headed, were pivotal in designing both controllers.
Even PC gaming is starting to see control innovations, with Valve's upcoming Steam controller. The first standardized controller designed specifically to handle traditionally PC-centric types of games, by offering a handheld device that attempts to bring the accuracy and versatility of a keyboard/mouse setup to the couch.
For some reason, the controller scroll wheel never really caught on.
When the idea of Nintendo "saving" gaming in 1985 with the Famicom and NES comes up, it is not uncommon to hear somebody mention that PC gaming never died and still exists to this day. While PC gaming has brought many innovations and continues to be one of the best platforms to game on, I would not want to trade away the contributions that consoles have brought to game design. Without standardized console controllers, many key innovations would not have caught on. The analog stick, never mind dual analog sticks, would not be as ubiquitous as it is today. Action games that require rapid use of many buttons would not exist, nor would games that require managing several shoulder buttons. For better or worse, gaming would be completely different. Even amid talk of mobile gaming gaining ground on traditional games, it's important to remember how important controller design has been for game design. Taking it a step further, standardized controllers that are well designed are one of the most important muses for any game creator. Knowing that a large number of people have this controller allows game designers to truly embrace the input device and make the most of what it brings to the table. Even the best mobile games make great use of the inputs available by default. Mobile games that try to play like console games work best with optional controllers that most people don't have, and suffer for it. I look forward to a future filled with new consoles, not just PCs and phones, precisely because of the power of standardized controllers. I look forward to seeing new innovations in the years to come that capture new audiences and bring new experiences. This has always been the greatest strength of the console market, and one of its strongest appeals to this day.