AI	Artificial intelligence; in game development, this can apply to individual actors (cars, soldiers, non-player characters, etc.) or to a computer-controlled opponent.
Alpha	The stage in a game's development where every feature is represented (often with placeholder content).
Balancing	Tuning game factors so that the proper difficulty is experienced by the player.
Beta	The stage in a game's development where every feature and piece of content has been implemented.
Build	An iteration of the game program and its associated data files.
Cinematic	A movie within a game; these come in pre-rendered and in-engine varieties.
HR	Human resources, the people who handle all the paperwork associated with having employees.
IT	Information technology, the people who take care of all the equipment infrastructure for a studio.
Localization	The process of translating all the text and voice elements of a game into another language.
Milestone	A defined stage in a game's development.  Usually, milestones include a set number of features/content, also known as a deliverable.  Milestones are very important for independent developers, as their contract with the publisher generally ties payments to the milestone schedule.
Modding	Creating "user modifications", which can range from new content for an existing game to so-called "total conversion" mods that change the game significantly.
QA	Quality assurance, the department responsible for testing a game in development and identifying any bugs in the software.
PR	Public relations, the people who represent the studio to the outside world.
Rendering	The process of converting game data into the images that appear on the screen.
Scripting	Placing actors, triggers, and objects within a game space and defining how these may play into various types of events.  Scripting is usually done in a simplified programming language.
Texture	A 2D color map that is applied to a 2D or 3D surface.
UI	User interface