AppImage : New package format for Linux
Debian/Ubuntu useing .deb packages,  Redhat, Fedora Using .rpm Packages. Now a days you can see a new package format .appimage
AppImage is a Universal package format  that runs in all the Linux Distributions.
It is very easy to use , because there is no dependency issues. 
A typical linux installation create files in various places so it requires root permission for installation.
but in appimage  doesn't need root privilege because it  doesn’t really install the software.
How to use appimage
  just download , make executable(right click on file --> select properties--> permissions and click on execute) and  run
Lot of Appimages are avilable here