TRANSLATION TO FRENCH MISSING
What is Arch Linux?
Arch Linux is an i686-optimized linux distribution that was originally based on ideas from CRUX, a great distribution developed by Per Lidén.
Arch is fast, lightweight, flexible and simple. Those aren't very fancy buzzwords but they're all true. Arch is optimized for the i686 processor, so you get more for your cpu cycle. It's lightweight compared to RedHat et al, and it's simple design makes it easy to extend and mold into whatever kind of system you're building.
Unique Package Management
This is backed by an easy-to-use binary package system - pacman - that allows you to upgrade your entire system with one command. Arch also uses a ports-like package build system (Arch Build System) to make it easy to build packages, which can also be synchronized with one command. Oh yea, and you can rebuild your entire system with one command, too. Everything is done quite simply and transparently.
Only the best
Arch Linux strives to maintain the latest stable version of its software. We currently support a fairly streamlined core package set with a growing collection of extra packages made by users and AL developers.
Simplicity is the key
In its goal to be simple and lightweight, I've left out the relatively useless portions of a linux system, things like /usr/doc and the info pages. In my own personal experience these are rarely used, and the equivalent information can be obtained from the net if need be. Man pages all the way...
Arch Linux also strives to use some of the newer features that are available to Linux users, such as Ext3/ReiserFS and udev support. Arch Linux 0.7 (Wombat) uses the 2.6 linux kernel by default, and has support for XFS/JFS.
Arch's Homepage is at http://www.archlinux.org/, where you can also find links to the user forums, official documentation, and everything else that is Arch. You can also read the TheArchWay for a bit more insight.