Should be mentioned that CentOs is no longer the “preferred distribution in the hosting industry” and has not been for a long time. That is simply a fake status, CentOS users would like to keep, but the reaility is one very different. Not even in VPS, Dedicated Servers or even Clouds. This also includes Red Hat in those different areas (Simple Hosting, VPS, Dedicated & Clouds). I will leave the following links for anyone to do their own checks but overall, Ubuntu covers well above the “preferred” term for all of this areas. So if you are looking for something that is applied in the industry, on the desktop, in the production stage but also in the development stage. If you are looking for something that is up to speed with latest technologies, openstack, deployment, and more, then please, one quick research for this will reveal Ubuntu above all others. In any case, I will leave the following for others to see and check for themselves.

Sources you can check out are as follow. I will also put the top 5 as of this writing where it applies:

W3TECHS - https://w3techs.com/technologies/details/os-linux/all/all
Ubuntu - 34.1%
Debian - 31.4%
CentOS - 20.6%
Red Hat - 3.7%
Gentoo - 2.7%

W3COOK - http://www.w3cook.com/os/ubuntu
Ubuntu - 29.9%
CentOS - 24.57%
Debian - 11.31%
Fedora - 0.68%
Red Hat - 0.01%

THE CLOUD MARKET - http://thecloudmarket.com/stats
Ubuntu - 57.5%
Windows - 7.8%
Red Hat - 4.8%
CentOS - 3.7%
Fedora 1.4%

OPENSTACK - http://www.openstack.org/assets/survey/April-2016-User-Survey-Report.pdf (Page 47)
Ubuntu - 55% (With an potential growth of up to 19%)
CentOS - 20% (With an potential growth of up to 7%)
Red Hat - 16% (With an potential growth of up to 4%)
SUSE - 2% (With an potential growth of up to 1%)
Debian - 3% (With an potential growth of up to 0%)

Even sources like Steam prove the amount of users compared to other distros that Ubuntu has, with 30% of all Linux users on Steam, followed by 9% which is a mix of other different distros.

http://store.steampowered.com/hwsurvey?platform=linux

Lastly the Linux Tendency over times shown here, clearly say what will happen in the following years:

https://w3techs.com/technologies/history_details/os-linux/all/y

https://www.google.com/trends/explore?date=today%2012-m&q=%2Fm%2F03x5qm,%2Fm%2F03x_8t,%2Fm%2F02prjf

i prefer ubuntu(easy) than RHEL.

i am not blindly supporting. i had my past experience.

we used RHEL 5/6 series.
we are web developers with ROR,postgresql,hadoop,golang(REST-API),angular2-dart,selenium,etc.
we were using puppet(server-agent) , chef(master-node-workstation) to replicate the infrastructure,
we used rvm/rbenv to install ruby VM.
but we have some issues with yum/rpm with RHEL.

for examples if we want to install latest rubies like 2.3.0 , it is little complex in RHEL.
because few c/c++ libraries will give dependencies issues like libyaml-x86-64,libyaml-i386,etc.
similarly we have many issues while updating packages to latest.
installing/uninstalling in RHEL is little headache .
we have more than 40 servers so we have to use puppet/chef.
there are many opensource puppet modules and chef cookbooks for ubuntu than RHEL.

recently we are migrated to ubuntu-14.04, which seems more stable release than the earlier.
it is very easy for us to code install/uninstall instruction for puppet/chef/Dockerfile,etc.
because apt source code repositories contains latest libraries.
apt package manager resolve many dependencies by itself, handling mismatch versions. with apt you can easily uninstall/remove pkgs.

apt repositories has latest source code for many of the open source technologies like ruby,rails,postgresql,golang, selenium,angular2-dart etc

recently we are moving to micro services, kubernetes,docker swarm, where we must have to use containers .we have to write many Dockerfile/s.
ubuntu is very suitable to work with Dockerfile/s docker containers, etc.
here again i prefer ubuntu than RHEL.

I choose FreeBSD, very easy to use, super powerful and secure, great community. Comes zfs, jails. bhyve, PF… it is just superior

I have used both (and am currently using both).

I much prefer Ubuntu, which I’ve been using for less than 6 months. I’ve been using RedHat (and Centos) for over 10 years. It’s only since switching to Ubuntu that I’ve realised just how Centos has been holding us back.

The problem is Centos is designed to be secure and stable, but as a result many things running on it are old versions, with back ported security fixes. If you’ve just spent a million dollars on an in-house software system, you don’t really want it to break a few months later because everything around it is always being upgraded to the latest and greatest. Really this is what Centos is all about.

However, we have always battled with not being able to run certain things on Centos because everything is so out of date. I think the default version of PHP is 5.4 on Centos7 and yet many people are now using PHP 7. It’s perhaps not a problem with an unmanaged service like Digital Ocean where you can upgrade things and take responsibility for it yourself, but if you have a managed service and have to stick with the official Centos Repos then you better get used to working with ancient versions of everything. From memory it also makes it a pain to run things like Magento and Laravel which often require newer versions of things than you’ll have access to on Centos (by default).

For me Ubuntu is a breath of fresh air and I would ditch Centos tomorrow if it weren’t such an upheaval to do so.

We have been using both - even currently. We have been in the development space for many years now. Do agree that lot many packages on CentOS are old but definitely very stable and secure.

I would say each of the Linux distros have their own pros and cons. Not only than it also depends on what you are comfortable with. You need to decide between Yum and Apt - or - Selinux and Apparmor.

When developing/publishing PHP based projects, we always prefer to use CentOS. We always use unmanaged services so there is no problem of sticking to older versions of PHP. We use PHP 7.1 / Laravel 5.4 without any problems on CentOS.

On the other hand, when we are working with Ruby based projects, we go for Ubuntu. It is rightly pointed above by thaniyarasu - we do face dependency issues with c/c++ libraries while installing certain newer gems on CentOS.

I use Ubuntu at home for my own servers (about 7 years working with Ubuntu and other Debian based systems) and in work we use CentOS (about 4 years on and off with CentOS).

My go to would be Ubuntu if you want to set something up, play around for it for a while then maybe close it down, without having to worry about getting everything up and running.

Like said before, Ubuntu has more up to date repos, and I for one would prefer that, but if I was setting up a server I know will be used long term (like the ones I set up in work) I would use CentOS without question, its repos are based more on stability and security and if you really want more fancy stuff EPEL is your best friend!

Ubuntu.

Everyone has their preferences, I like CentOS but i use Enterprise Linux daily. Ubuntu fits in on some places but i think overall CentOS is more stable and secure. Just my opinion

I think Ubuntu has the brightest future. As Ubuntu desktop is the most commonly used linux on desktop/laptop. Those users will naturally choose Ubuntu server.

Also ubuntu has a very strong backup and their software updates are fast.

What can someone with no prior knowledge about the two do?

Hey all. Fedora (upstream/development/testing) is working on what they call “Modularity”. If you’re worried about software, you can install a different package manager, such as nix (but this usually requires configuration, and I assume few people care… Ubuntu is definitely the most complex when it requires editing configuration files), but this is what Fedora is doing:

• A package is up for addition or removal. Every distro has their own package managers. Nothing new.
• Once a package manager (person) decides to update the package, it goes to koji (the buildsystem) and gets built.
• Every release has its own repository. RHEL 6/7 and CentOS 6/7 share EPEL 6/7 (“Extra Packages for Enterprise Linux”; shared because CentOS is Red Hat without the branding or paid support, although there are some things going on where CentOS is considered upstream for some development initiatives), and Fedora has 26/27/28 (with Rawhide being the highest-tier development… right now, the release is 27, and 28 just entered ‘branched’, and rawhide is development).
• Here’s where it gets interesting: Fedora is calling their move to unify the buildsystem and integration of packages (e.g. python-2 and python-3 can exist separately and not break anything) “Modularity”. Fedora is hands-down the best distro for integrating new packages (like Wayland to replace X.org), but the buildsystem places these packages in each repo. Modularity allows implementation across all platforms (Fedora 26/27/28/EPEL).
• In function, this will all be its own repo. System repos & packages (ex. cent-base) won’t be harmed, and if a user wants to install different Rails stacks, that’s perfectly fine.
• My personal hope is that this becomes more convenient than tracking these things down on their own. For example, I can get python 3.6 on my CentOS machine through those “extra-community” repos like RPMfusion (free and non-free) and IUS (which is prettymuch up there if I can get 3.6). But I get it seems tedious, and I get some people assume it won’t work because it’s not vertically integrated, Apple-style.

As for my other thoughts on Ubuntu:

• Desktop has nothing to do with server. Canonical gets too much crap for going their own way with things like Unity and Mir. These are dead projects since Canonical decided they were losing revenue and just couldn’t feed the bear. I also prefer SELinux to AppArmor.
• Canonical does some really great stuff, though. They’ve made Snappy, which is like Flatpak (they started around the same time, but I know GNOME had stuff going on in '13). Canonical basically runs LXC & LXD, which used to be big because of Docker. It’s not really important for your purposes, I assume, but just know that packaging and packages have little to nothing in this choice. Debian has a tool called “alien” that can convert .deb’s to .rpm and vice versa. But Steam and Spotify are the only programs I know about that are published only as .deb. If you care about servers, it won’t matter, because every major distro is trying to solve the packaging problem. (Containers are amazing!)
• Ubuntu makes life a pain for development. I like configuration files, but I don’t want to go through everything. Some projects will edit your config files for you, like Let’s Encrypt for nginx on my Cent http server, but you have to be pretty involved already if you want to script.
• I guess I respect Ubuntu users for their popularization of the linux desktop (and support by software companies, since Steam allowed more gamers to switch - or at least we should acknowledge that SteamOS bases itself on Ubuntu, even though I prefer Steam on Fedora). However, I want to stress that the only differences that matter to servers are how the developers feel with the system. I don’t need extra cruft in my system, and I know my way around CentOS. Neither are hard to learn, I mean a distro is literally the linux kernel plus all the required programs (like the GNU make, autoconf, tar, etc., and the package managers and daemons). CentOS doesn’t default to run things I don’t want, and I’m happy with that. I’m happy with rpm and systemd, and it all just works.

The differences between the two don’t matter. I would never install Ubuntu “because that’s the only way I know how to use Apache”. Remember, everything is open source, and anything that is GPL/MIT/BSD/similarly licensed also includes documentation. First you’ll learn about protocols, then you’ll learn how those are implemented. You’ll learn web servers before you have any opinions about LAMP vs LEMP. You’ll learn HTML, CSS, maybe JS, a long time before you choose to make something with Django. You’ll learn about files and permissions and relationships long before you care about Wordpress vs Drupal (or Joomla).

I challenge you to get straight into it. 2015 was a long time ago. Whoever’s reading this might choose Ubuntu because I seem militant and I seem to adore Cent. Either way, just get one and install something. Say install Docker. They’ll help you out. Everything is there. It’s all documented. Just about every piece of software has installation and “getting started” instructions.

Enlightening answer, thank you.

Just now I have gone through one article and I think it help you guys as well!

https://itmunch.com/red-hat-vs-ubuntu/

CentOS by and far. More stable out of the box, not riddled with things you do not need