Here, in alphabetical order, is a list of the seven distributions that have most affected GNU/Linux as a whole…
And Debian is here
Debian has a reputation for being hard to install and use, neither of which is true today. The new Debian installer released a couple of years ago has taken the pain out of installation, while the prevailing ethos today seems to be to accommodate all levels of users from newbie to expert. Similarly, the frequent complaint that official releases are slow to emerge is largely irrelevant, since most users can get the latest software simply by installing from the appropriate repository.