When we, as designers, consider our games, there is one thing that is absolutely paramount to get right. Graphics sell games, but make them they do not. Sound (esp. music) elevates a game and gives it a rich tapestry of flavour, but isn't strictly important. Story can be taken or left, in any amount, to any effect. But there is one part of a game that absolutely must be done right for it to succeed: The interface.

Games are interactive. That is the primary defining trait that separates games from other text. So when it comes down to what makes a game special, it must necessarily include that most important of traits.

Think about the history of games. Those games that stood out from the rest, and are iconic examples of the medium. The grand majority of these games share a common trait - the interaction was a primary defining point. Asteroids, Breakout, Pong, Command and Conquer, Doom, Unreal, Total Annihilation, Halo, Guitar Hero, World of Warcraft, etc. all pioneered new, revolutionary or evolutionary interfaces. This is not to say that they weren't brilliant in other ways, just that in this way, they were accessible and extraordinarily comfortable to use. World of Warcraft, as a case in point, took the confusion and complexity out of the interface, and it led to MMORPGs taking the world by storm. Halo took the previous work of Goldeneye and built on it, until it had a FPS that actually played WELL on a console.

A game's interface is the way a person interacts with the game. It takes several forms. The "Graphical User Interface" (GUI) is what many people immediately think of when they think of an interface. The GUI is important, in that it layers a level of logical abstraction on top of the number crunching going on beneath. For instance, a health bar allows the player to visually gauge how much health they have left, without the need to compute the numbers. This makes the game flow faster and be more immersive. RPGs tend to have icons representing abilities and spells. This should give the player a quick idea of the general purpose of the ability, and again it hides the numbers and words that would slow playtime. RTS games almost universally use icons to represent troop types, for the same reason.

But there is another, very important reason why GUIs are good: they add a layer of fluff. By fluff, I mean atmosphere. It doesn't impact on the actual gameplay at all, but in some strange way makes it better, and infinitely more playable. This is partly for that hated word "immersion" (more on that later) and partly because of the above - on some level, it makes the interface easier to understand.

But Interface isn't necessarily limited to the GUI. There is the more direct interface of the control scheme, and a lot of effort goes into making the controls feel fluid and responsive. By doing simple things like putting buttons in obvious places, and maintaining conventions used through other games, designers can tap into motor functions, and spare the user from having to conciously think about how to interact with the game.

There are two ways information is shared in an interface - information given to the user (output) and commands given to the game (input). Both of these elements need to be given equal attention if the game is to be as amazing as it should be.

The interface is sadly, at the back of the mind for many Game Maker users. Many games fall short of excellent for this very reason. If the player needs to work to interact with the game, there will be a barrier between them and fun that will be very difficult to take down.

Instead of going into strict detail here, I'd really like your thoughts as to what makes a good interface though - we are, after all, here to discuss game design and learn from each other. In future, I'll be dissecting a few interfaces I've worked on before, so keep an eye out.

I'll leave you with the following link. It lists ten heuristics (guidelines) to good interface design. It is used often in the industry as a checklist of sorts.

http://www.useit.com/papers/heuristic/heuristic_list.html

Comment away!