Arch is based on Rolling Release model, which means you don't have to upgrade the system every once 6 months or so. It keeps on updating through packages itself, and therefore does not contain any proper version number.

Arch has its Arch User Repository (AUR), which contains pretty much all the packages you will need. Most software built for Linux will be available in AUR, which therefore is easy to install.

You install most of the software by yourself (Desktop Environment, etc.) so you are in control of how things look and feel.

Arch Wiki is probably the best Wiki around. Most of the problems which you might encounter are detailed in the Arch Wiki thoroughly.

You have to build a lot of the OS yourself according to how you want it to work. That requires configuration which in turn requires understanding of some of the working of the OS. Therefore, it teaches quite a bit of how it works.

Arch Linux is a bleeding edge distribution - meaning, it has latest packages/software in its repository.

Since its stripped down, it is fast and you don't have to deal with bloatware.

If searching through the wiki or the forums for any problems turns nothing, any question on the official forums, Arch subreddit or the IRC channel will be answered within minutes. There will probably be no hand-holding however, Arch users prefer to point anyone to a resource that may help them instead of trying to outright solve their problem in a forum thread. This is quite helpful for people who want to really learn how their system works but also for other people who may stumble in that thread considering how most problems don’t have a universal solution.

There are extremely helpful 3rd-party installers such as Anarchy Linux (Formerly Arch Anywhere).

The design approach of the development team focuses on elegance, code correctness, minimalism, and simplicity, and expects the user to be willing to make some effort to understand the system's operation.

From latest wacom pads to obscure wireless cards in laptops Arch's hw support has been and continues to be good. It has worked on laptops where other leading distro's like debian/ mint/ ubuntu failed to detect and work with all hardware.

The AUR is a repository with a very extensive catalogue of build/install scripts that are contributed by users. While these scripts are inherently less secure than conventional packages maintained by a distro's authors, it's still way easier to verify the security of install scripts than it would be to write them yourself. It's very usefull.

Pacman has performance advantages over apt-get and yum in both database operations (thanks to being written for speed) and download times (by virtue of using better mirrors than other distributions tend to select by default). There are also fewer default repositories to download from, and all package management is combined into one tool instead of being split into dpkg, apt-get, and apt-cache like on Debian distros.

Arch keeps its core repositories slim and free of unnecessary dependencies. At first installation only a bare system is set up. You can easily get the other applications through the package manager. The repositories are nearly as full as those of Ubuntu, while they are often more up to date. That way you don't have to waste time with software you don't need or want.

Arch is mainly aimed at experienced Linux users, there is no hand-holding and not much in a way of UI elements when trying to install or tweak settings.

If you need to install something, chances are someone in the Arch community has already made a package for it. This makes it incredibly easy for you to install and maintain all of the non-media content on your computer.

Arch's goal of simplicity means there's usually one preferred way to get things done - through organized and well documented configuration files. This focus, combined with the community's recognition that configuration files can be intimidating, has resulted in excellent documentation that's accessible to newcomers, and very instructive about how Linux actually works. The documentation is often so thorough that, when searching for solutions to problems while using other distributions, such as with video card drivers, oftentimes you'll find the most effective solution in the Arch Linux wiki or on the forums.

Since you install the OS as and how you want, you can make it as minimalistic as you like, which in turn would make the system's use of resources quite low.