Why should you use CentOS or fedora instead of Ubuntu?

Question

ubuntu

What is their peculiarity or specificity?

Answer 1

Here, in matters of what or whom, there is a lot of its own specifics.
For example, as Ivan Bogachev said - the availability of repositories.
On the other hand - versions, personal preferences and available software versions.
For example - I like to use CentOS 6 because of the classic start system. I find CentOS 7 a very poor build. There by default there is no instrumentation habitual to me. On the side of CentOS - stability but not the newest versions of software by default. Puias to help all the Red Caps. But there are sometimes jambs.
Ubuntu (I'm only looking at LTS builds) is a stable selection of more recent software. Plus, some things are collected there more successfully (For example, strongswan - all plugins are in separate packages). The same Edubuntu provides a doped LTSP.
Here the choice is goal-oriented. Whatever solves the problem better is more suitable.