Field of view (FOV) is a setting used in PC games to denote how far your character can see in his peripheral vision. The approximate human FOV is about 95 degrees to either side of the nose. For some people (myself included) low FOV in PC games (first person shooters exclusively for me) can cause headaches, eyestrain, and/or nausea. This is because the brain is not meant to see through such a low FOV. I was recently playing a game (Orion: Prelude) which had no FOV options and was locked at, I'd say about 60 degrees, and after 30 minutes of play I started to get a bit of a headache. This FOV is fine for consoles, since you sit farther away from the screen, but with PC games you sit closer, and it therefore takes up most of your vision. So, if you're a PC developer, include FOV options in your first-person shooters!
If there's no direct FOV setting, depending on the game there's still possible ways to change it. Console commands, editing the correct config file where the game was installed, etc. With multiplayer games this can get you banned obviously, depending on how strict they are.
It's silly that a necessary setting can get you banned in some games (*cough* Call of Duty). FOV is as important as colorblind options. With some games, there's no config settings to edit the FOV, and no hacks that have been made yet. And I have a quick correction: Orion does have an FOV setting, but you must go into the command console.
Only main reason that it would get you banned in multiplayer games is an increased FOV could definitely be an unfair advantage over other players. Single player doesn't really matter to them. And yes, not every game's config is immediately human readable, settings could be stored in a binary format.
