Linux Distributions (Distros) 

Choosing a Linux Distro and why to use which version / OS?

Why use Ubuntu?

UBuntu: It works like Mac OS and easy to use. 

Why use Linux mint?

Linux mint: It works like windows and should be use by new comers. 

Why use Debian?

Debian: It provides stability but not recommended to a new user.

Why use Fedora?

Fedora: If you want to use red hat and latest software. 

Why use Red hat enterprise?

Red hat enterprise: To be used commercially.

Why use CentOS?

CentOS: If you want to use red hat but without its trademark.

Why use OpenSUSE?

OpenSUSE: It works same as Fedora but slightly older and more stable. 

Why use Arch Linux?

Arch Linux:  It is not for the beginners because every package has to be installed by yourself.