4. Introducing Linux¶
Linux is a UNIX-like operating system for computing-devices, from regular desktop pc’s down to embedded platforms and smart-watches and smartphones up to supercomputers and enterprise datacenter solutions. The Linux world is made up of various ‘distributions’, each with their own focus, methodology, target audience and philisophy.
In this book we will mostly focus on the CentOS, Red Hat, Debian and Ubuntu Linux distributions, as these distributions are most commonly used in business settings and have large target audiences.
4.1. CentOS and Red Hat¶
Red Hat is a company that creates a Linux distribution focussed mostly on business and enterprise use. They are one of the main developers working on new Linux features, employ a lot of Linux developers and have a policy of releasing all their products under Open Source and Free-Software licenses. Red Hat sells support for Linux using businesses and targets the Red Hat Enterprise Linux (from now on: RHEL) distribution on large business users of Linux.
CentOS can be considerd a fork or derivative version of RHEL, and is mostly used as a free-to-use alternative to RHEL. CentOS is created by a group of people, mostly working for Red Hat these days and is mostly used in Cloud environments and smaller businesses where support from a large vendor is less critical.
Since RHEL and CentOS are built from the same sources and target the same platforms and features, both distributions can mostly be used interchangable. The only technical difference between both distributions consists of the subscription-related software and configuration present in RHEL, which is not available or needed in CentOS.
Debian is one of the oldest available Linux distributions, and also contains the one of the largest sets of available software packages. Debian is built as a community-project run mostly by volunteers and some people from various Linux using corporations who are employed to work on Debian either full or part-time.
Debian’s main strenghts are it’s large selection of packages, quality of the packaging and choices it provides to it’s users. Debian has a strong free-software philisophy and makes it possible to install a completely ‘free’ system. Support for debian is available from mailinglists, forums and various other platforms, and various companies can provide paid support. The Debian-LTS project also provides longer-term (paid) support to older versions of Debian.
Ubuntu was originally a desktop-focussed distribution of Linux that starts from a debian-base and built on from there. These days Ubuntu is used a lot on Cloud-environments, by software-developers and enterprises. Ubuntu and Debian functionality is mostly comparable, and with knowledge of one you will feel mostly at home on the other.