Download an application, make it executable, and run! No need to install. No system libraries or system preferences are altered. Can also run in a sandbox like Firejail.
Most AppImages run on recent versions of Arch Linux, CentOS, Debian, Fedora, openSUSE, Red Hat, Ubuntu, and other common desktop distributions.
Distribute your desktop Linux application in the AppImage format and win users running all common Linux distributions. Package once and run everywhere. Reach users on all major desktop distributions.
“As a user, I want to download an application from the original author, and run it on my Linux desktop system just like I would do with a Windows or Mac application.”
“As an application author, I want to provide packages for Linux desktop systems, without the need to get it ‘into’ a distribution and without having to build for gazillions of different distributions.”
Please see https://github.com/AppImage/AppImageKit/wiki