Most commonly recommended Linux distributions use GNOME or KDE. These two environments dominate the market, although alternatives like XFCE and Cinnamon have existed for years. There really isn't a single desktop environment built specifically for any particular distribution or hardware.
If you've been following Pop!_OS, you may know that the development team has been working on their own Rust-based desktop environment since 2021, and now that it's finally launched, COSMIC looks like a strong option for many.
COSMIC marks a turning point for System76 from GNOME.
It's similar to both the kernel and the desktop environment.
On Linux, the desktop environment is essentially what you interact with every day. It's the software that controls the entire user interface and the overall look of the system. When experimenting with different distributions, you've probably encountered the most popular choices, primarily KDE and GNOME .
If you've ever used Pop!_OS before, you've probably noticed that it uses GNOME, similar to what Fedora uses by default. However, System76, the developer of Pop!_OS, never actually ran GNOME natively. They added their own tweaks, particularly around features like window management and customization.
COSMIC is a brand new desktop environment written in Rust by the same people. It retains the familiar GNOME-style layout, but adds features like window tiling, configurable panels, and you'll be surprised to find it's quite similar to previous versions of GNOME.
Note : It's also worth noting that COSMIC isn't exclusive to Pop!_OS. While it's the default operating system there, you can install and use it on other distributions.
Many people have used it with the COSMIC version of Fedora, and it's also an option with CachyOS , one of the best lightweight distributions you can try. Obviously, you can even install it yourself on any other distribution.
You'll find it familiar right away if you've used Pop!_OS before.
It's not very different (in terms of appearance).
If you've used Pop! OS before, COSMIC won't be much different when you first start it. The overall layout and workflow remain quite similar, which is intentional. COSMIC isn't trying to create an entirely new design language; GNOME has already done that quite well. The focus is on performance, not on overwhelming the user.
Instead of adding numerous extensions on top of an already cumbersome GNOME operating system, COSMIC provides all those features natively. Previous versions of Pop!_OS relied heavily on extensions to add features like window tiling and other workflow tweaks, which worked well, but were certainly resource-intensive by Linux standards.
The same applies to things like the dock. You still have all the familiar options, such as moving it to the left side of the screen or allowing it to stretch across the entire screen. Nothing new if you've used Pop!_OS before, but it's now much faster and more responsive.
You have countless customization options.
You can make it look great. or terrible.
This is definitely one of the best parts of COSMIC. You can change the colors of most of the main UI elements, similar to how Google 's Material Design works or how you can add app icon colors on iOS. And no, it's not limited to just choosing accent colors.
Along with the usual accent color options, you can also choose distinct colors for window backgrounds, interface text, buttons, input fields, etc. Once these changes are applied, they will automatically be applied to all COSMIC applications. However, keep in mind that it does not work with most third-party applications.
Remember, it's easy to get carried away and end up creating a disaster like the fifth image above.
Tip : However, one thing many people will definitely change is the default font. COSMIC uses Open Sans, a font that isn't very suitable for the whole system. Replacing it with a more modern font is definitely worth doing in the first place.