Recs.
Updated
Debian is available in three releases (stable, testing or unstable which can all be installed as a rolling release(by replacing the releases name(eg: stretch) with the code name(eg: testing).
SpecsUpdate
Pros
Pro Wide choice in desktop environments
Debian offers stable and testing CD images specifically built for GNOME (the default), KDE Plasma Workspaces, Xfce and LXDE. Less common window managers such as Enlightenment, Openbox, Fluxbox, GNUstep, IceWM, Window Maker and others can also be installed.
Pro Easy to find help with any problem
Debian is one of the oldest and most popular distros out there. Debian's popularity means that you will always be able to find a solution for your problem just by searching on Google, or if by chance nobody has had the problem you are having it's very easy to ask the community and quickly get a solution.
Pro Standard vanilla Linux desktop
Debian runs standard Gnome, XFCE, KDE - it doesn't use its own special desktop environment, which means that users benefit from the work of the whole Linux community, Debian developers can focus on the distribution itself, and any support for your desktop environment on other distributions should work on Debian as well.
Pro Comes with over 37,500 packages
Because of its popularity, Debian has a lot of applications available which range from productivity programs to business software, games and development tools. It comes with over 37,500 packages (software that is precompiled and ready to be installed on a local machine) -- all of them for free.
Pro Extremely easy to find help with any problem
Debian is one of the oldest and most popular distros out there. Debian's popularity means that you will always be able to find a solution for your problem just by searching on Google, or if by chance nobody has had the problem you are having it's very easy to ask the community and quickly get a solution.
Cons
Con No default support for non-free hardware
Non-free hardware will not work upon install of Debian and the user will need to search out the correct non-free software to install in order to make them work. This can be difficult if one of the things not working is the WiFi connection.
Con High quality standards that hinder adopting new software
Not really a bad thing however, it takes some time until new applications find their way to the official repository. If you plan to add a package by yourself, you first need to become a Debian maintainer. After that you need to follow the Debian package guidelines and so on.
Con Not very stable.
Testing branch of Debian is not as stable as the stable branch. You will often get dependency issues.
Con Apt(-get) package manager can be temperamental
Seemingly more of a problem on Ubuntu, nevertheless the default package management system is prone to breaking on both Ubuntu and basic Debian. This can have critical, system-wide implications and require a lot of time and very advanced knowledge of Linux to even begin debugging.
Con Not a rolling release
why is this here in a list of best rolling releases, when debian is not a rolling release?
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Comments
Flagged Pros + Cons
Pro A flavor of Debian
It's a 'normal' Debian with official Debian repositories. Works like Debian, behaves like Debian.