Introduction
It seems that every 3D Shooter has a file or files which contains all of the game's graphics, levels, sounds, sprites, etc... Let's see, Doom, Doom II, Heretic, and Hexen with .wad files, Dark Forces with .gob files, and Duke Nukem 3D with .grp files. Well, Quake is no exception. It uses two .pak files that contain all of the game's data. The two pak files that Quake uses are Pak0.pak, which contains everything as the Shareware version, and Pak1.pak, which contains the rest of the information for the registered version which the Shareware version does not. The Pak file is like a Zip file that when unzipped, or unpacked, goes into directories containing the information. Here's an illustration of the Pak file is made up.

I'll explain whats in each folder now. The gfx folder contains all of Quake's menu and console graphics(.lmp). The maps folder contains all of Quake's maps(.bsp). The progs folder contains all of Quake's 3D Models (.mdl), Configuration Files (.cfg), Screen Shots (.pcx), and the progs.dat file, if you have some QuakeC you want to use, place the Progs.dat file where it is as shown in the picture. You can create a .pak file yourself, but sometimes there are certain things that won't work in Quake when packed.

Creating a Pak File
Creating a .pak file is simple. Just download and execute my Setup Batch File which sets up Quake for running add-ons easily. After creating all the files you want to use for Quake, put them in the proper directory and then use AdQuedit, and get the Manuel, select the root directory and go to File>Create Pack. That was easy was'nt it? Note that if you choose to create a .pak filem then all the folders and files must begin with lower-case letters. AdQuedit will build a .pak file with capital letters but Quake won't run it. PakExplorer will make files lower-case automatically. I really reccomend getting PakExplorer. This great little utility is better for creating .pak's because of features such as browsing and inserting more stuff without having to pack the whole thing again, but be careful when dragging files out because it moves them out, not copies, and will cause Quake to crash if it can't find a required file. My example contains a .pak file with examples of everything on my editing pages, so if you want the stuff in it or any other .pak file, you're all set!