A

• AI - Artificial Intelligence. Every character other than you is controlled by the game's AI.

B

• Bug - A programming error in a game or application that was missed in software testing. Most gaming manufacturers put out patches, or fixes to correct bugs found after release.

C

• Clock Speed - The actual time that certain functions take. A processor at 100MHz processes one million cycles for every second of time.
• CPU - Central Processing Unit

D

• Demo - a preview of a game. Most companies now make free demos available for new games that include one or 2 missions or scenarios for potential buyers to preview.

E

F

• Flight Stick - A joystick/or controller modeled after the actual flight stick of an airplane/jet.G
• FPS - First Person Shooter. A game where you're looking through the eyes of the main character of the game.

G

• Game Pad - A popular controller that had direction pads and buttons used to maunver through the game.
• Genre - A specific category of games. i.e. Fantasy, Science Fiction, Horror, World War II, etc...
• GHZ - Gigaherz. The newest CPU are now starting to be measure by this. One billion cycles per second.
• GPU - Graphics Processing Unit

H

I

J

• Joystick - similar to a flight stick this basic game peripheral is used as directional and gameplay controller.

K

L

M

• MHz - Megahertz. Most PC CPUs are measured in megahertz. One million cycles per second.

N

• Newbie - Someone new to the game or computer games in general. Used in many gaming chat rooms to describe someone's level of play.

O

P

• Patch - An piece of code usually release by the manufacturer of a game to fix bugs that were found after the initial release of a game.

Q

R

• RAM - Random Access Memory. The amount of memory your CPU has to store applications that it is currently running.
  

S

T

• 2D - Two Dimensional.
• 3D - Three Dimensional
• Third Person Top Down - Type of game where you're looking down ontop of the action from a "third person point of view"
• Tutorial - Most games have a tutorial or "in game instructions" where it will walk you though basic gameplay without having to read a manual.

U

• USB Port - Universal Serial Bus Port. Used as interface between many computer gaming peripherals such as joysticks and gamepads.

V

• Video Card - aka Graphics Card. A piece of hard wate that intefaces witht he computer's motherboard for the rendering of graphics.

W

XYZ