A camera is an entity in the game that allows players to view what is happening in the virtual world.
Guild Wars' only camera options are vector facing and zoom. Most other games have options that modify the angles or movement control of cameras.
Guild Wars' camera operates on three separate axes XYZ, with X (radial) controlling horizontal movement, Y (radial) controlling vertical movement and Z (linear) controlling zoom. Z's distance from the player is measured in an unknown unit that is always a positive rational number ranging from 25 (zoomed all the way in) to 750 (zoomed all the way out). This range cannot be artificially changed (through the use of, for example, a memory scanner or an in-game trigger; an attempt to input a value that does not qualify results in the value being rounded to the nearest applicable number: inputting -3, for example, results in the value of 25). It assumed that the in-game cinematic cameras that allow for further zoom in fact either A) reposition the character in mid-air (which the system does permit) or B) use an entirely different camera mechanic, one that may be more difficult to access.
X and Y operate on radians, which befits their nature as radial axes. These cameras will permit "incorrect" values, which are compensated for by adjusting the camera until a satisfactory radial value is reached -- in-game, this can be observed as a very rapid spinning of the camera along the given axis. Negative values will result in the camera spinning in the opposite direction.
Camera information is stored client-side, not server-side. It is unknown whether ArenaNet is able to observe or access a player's camera usage.