The "One Sheet".

This is a single page description that outlines the games main goals and vision. Designers, Artists and Programmers should all be the intended audience.

The "Design Doc".

This is a multi-page document that outlines the features and specifications needed to achieve the goals and vision of the game as outlined in the "One Sheet". Designers, Artists and Programmers should all be the intended audience.

The "Design Bible" This is the biggest document of them all. After the design document artists and programmers should have all the information they need to do their jobs so from here on out the documents are generally aimed at other designers and content guys.This is an in depth write up of all the content in the game from a designers perspective. All the missions, quests, characters, events etc. should be in here (but not explicitly). This document usually has many owners and is more commonly put into the form of a wiki.

The "Technical Design Doc".

This is the document (usually written by the lead programmer) that examines the features and gameplay laid out in the "Design Document" and beings a technical analysis of what needs to be done to get said features to work. Usually written in some weird moon language. For Programmers only

 

The "Script".

There's usually several of these. One per mission, quest or level and is a write up of all the chacters, dialog, and events. This is the most specific document in terms of content and should be a resource to anyone looking for any specific information on a certain part of the game. Also should contain a walkthrough.

This is the beginning of a long list of boring documents ;) Ideally one for each major subsystem (Physics, AI, etc). The idea is that as you go down the chain, the documents get more and more specific to an area until all the questions are answered.

The "Art Guide".

Based on the technical specifications written out by the programmers this is a document written by the lead artist that covers not only style and mood considerations, but also technical practices that all artists should follow. This is anything from polycounts to exporter settings and how to get the art into the game.