RPM Based : Red Hat / Cent OS / Fedora / Suse / Qubes OS / Mandrake ...
Red Hat and SUSE were the original major distributions that used the .rpm file format.
DEB / DPKG Based : Debian / Ubuntu / Kali / Mandriva / Backtrack ...
Debian were the original distributions that used the .deb file format.
Many other formats exist like :
Mepis Based / Knoppix Based / Pacman Based / Gentoo Based / Slackware Based ....
Comparison of Linux distributions (Wikipedia)
Actually (2018), the percentage of use of these OS is approximately :
Debian 45% / Red Hat 20% / Ubuntu 20% / Others 15%
To check your OS Version type in command line (Terminal/Shell) : uname -a
For a Debian based system, you could do : cat /etc/*_version
For a Red Hat based system, you could do : cat /etc/*-release
List of Website page with more information about versions / distributions :
Wikipedia : https://en.wikipedia.org/wiki/List_of_Linux_distributions
Distrowatch : https://distrowatch.com