Debian is one of the distributions that most originated other projects, just to mention a few examples, we can put in a short list Kali Linux, Ubuntu, SteamOS, Tails, among many, many others! Debian, not as «the father of all», but of many, decided to catalog its «children.»
Debian, together with release of version 9, Stretch, also launched a page to try to gather important information about the Linux distributions that are derived from it, both to inform people and to publicize these projects.
The “census” page also shows a lot of information about projects derived from Debian, as they explain in the documentation. Examples are given of what is different in each system in relation to Debian and in many cases also commenting on what the projects have in common and how they relate and help each other. This Wiki page Debian should also receive constant updates, adding more and more distributions. You can collaborate yourself, just follow the instructions contained therein.
Debian decided to show off his “kids” a little bit more, and given the list, with so many cool projects, he certainly must be a proud “dad”.
To the next!