I find this
Wiki wrote:Computer graphics
Frame rate is also a term used in real-time computer graphics systems. In a fashion somewhat comparable to the moving-picture definition presented above, a real-time frame is the time it takes to complete a full round of the system's processing tasks. If the frame rate of a real-time system is 60 Hertz, the system reevaluates all necessary inputs and updates the necessary outputs 60 times per second under all circumstances.
The designed frame rates of real-time systems vary depending on the equipment. For a real-time system that is steering an oil tanker, a frame rate of 1 Hz may be sufficient, while a rate of even 100 Hz may not be adequate for steering a guided missile. The designer must choose a frame rate appropriate to the application's requirements.
I like the example here.
and this:
Wiki wrote:In modern action-oriented games where players must visually track animated objects and react quickly, frame rates of between 30 to 60 frame/s are considered minimally acceptable by some, though this can vary significantly from game to game. Most modern action games, including popular first person shooters such as Halo 3, run around 30 frames a second, while others, such as Unreal Tournament 3, run at 60 frames a second. The frame rate within games, particularly PC games, typically varies with the hardware configuraton, and depending upon what is currently happening in the game at a given moment. When the production of a frame makes large demands on the CPU and / or GPU, the framerate falls.
The first sentence states more of an opinion. Then gives some examples with Halo 3 running at only 30 FPS, I assume Xbox 360 specs, and UT3 at 60 FPS.
Though Hz is a little different from FPS. Maybe they can be used interchangeably, not sure. I take Hz to mean what the monitor itself can handle, while FPS is what is being outputted from the system. This would mean that there is no reason to run a game a 300+ FPS if your monitor can only display at 100Hz. You would be losing 200+ frames and thus taxing your GPU for no reason.