3.1. Introduction

Debian is known for being extremely stable and reliable, and for its excellent package manager/dependency resolver, apt. Installing a new application is this simple:

# apt-get programname

All dependencies will be automatically fetched and installed. Not only is apt a sophisticated, intelligent tool, but the official Debian software repositories maintain strict packaging standards. The official Debian repositories contain over 12,000 programs, more than any other platform.

dpkg is RPM's Debian cousin, with an extra ability: dpkg also performs basic configurations. For example, when you install Postfix, dpkg will ask you for some basic system information, install startup files and configuration files, and fire it up.

Debian has three different releases: Stable, Testing, and Unstable. (There is also a fourth release for the adventurous, Experimental.) These are also known as Woody, Sarge, and Sid. Woody is extremely conservative. Packages are accepted into Woody only after extensive dependency testing and security patching. Sarge and Sid contain newer, less-tested releases. Security patches are swift for Woody and erratic for Sarge and Sid.

Which release should you use? The obvious choice is Woody (Stable). It's rock-solid. However, this stability comes at a price: programs in Woody are months, sometimes years behind the latest releases. Woody is great for servers. For desktops and workstations, Sarge (Testing) and Sid (Unstable) are more up-to-date. And despite the scary names—"Testing" and "Unstable"—they perform just fine.

As cute as the code names are, they shouldn't be used in configuration files. Unstable will always be Sid, but Woody and Sarge will not always be associated with Stable and Testing—someday the current Testing release, Sarge, will be promoted to Stable, and the current Woody will be retired. A well-maintained Debian system can be continuously upgraded forever and ever, without ever needing to be completely reinstalled, so you don't want to goober it up by using release codenames that will change.

These are the release codenames, all taken from the movie Toy Story:

"Buzz"—Buzz Lightyear, the spaceman (1.1)

"Rex"—Rex the tyrannosaurus (1.2)

"Bo"—Bo Peep (1.3.x)

"Hamm"—Hamm, the piggy bank (2.0)

"Slink"—Slinky Dog (2.1)

"Potato"—Mr. Potato Head (2.2)

And for the 3.x releases:

"Woody"—the cowboy (Stable)

"Sarge"—the leader of the Green Plastic Army Men (Testing)

"Sid"—the rotten kid who destroys toys (Unstable)