Univention Corporate Server (UCS) and Univention Corporate Server @ school (UCS@school) are Debian derivatives, i.e. operating systems derived from the Linux distribution Debian GNU/Linux. So, what exactly is Linux, what is a Linux distribution, and what does derivative mean? Read on to find out more about these terms and the connection between UCS and Debian GNU/Linux.
What is Linux?
Most people say “Linux” and mean an operating system which is not 100% correct. Strictly speaking, it’s the kernel that’s called Linux. The kernel is the actual core of the system. It controls the computer’s hardware, for example the processor(s), the memory, and other peripheral devices. The kernel manages the resources and works as an interface to system and application programs, i.e. it controls their start, stop, I/O (input/output), and memory access. If necessary, the kernel can reload appropriate hardware drivers for new devices; in Linux, the drivers are called “modules”.
It was in 1991 when Linus Torvalds initiated the Linux kernel. He announced the project on Usenet as “just a hobby, won’t be big and professional”. He couldn’t have been more wrong: today, thousands of developers all over the world are involved, and the kernel is far from being a hobby. The number of code lines has grown from 10,000 (version 0.1) to about 25 million (version 5.0). Everybody is allowed to contribute to the kernel, but the final decision about the code is made by a few lead developers, Linus Torvalds still being one of them.
You can’t do much with just the Linux kernel – you also need system and application programs. Most of those programs originate from the GNU project (“GNU’s Not Unix!”) that used to have its own kernel, but is mainly used with the Linux kernel now. The additional software, and that includes the installation program, often comes pre-packaged, sometimes with a manual or other documentation. The complete bundle is called “distribution”.
What is a Linux Distribution?
So, a Linux distribution includes the kernel, basic tools and programs as well as an installation routine. There are pre-packaged boxes available that contain installation DVDs together with a manual. Alternatively, you can download ISO images from numerous download sites on the web.
It’s a long and confusing list of Linux distributions – which one should you use? The DistroWatch website might help. It gives an overview of Linux systems and lists popular distributions. The ranking is being calculated by counting the number of page hits of the distribution pages on DistroWatch itself; only one hit per IP address per day is counted.
There are Linux distributions for many different purposes. In addition to so-called live distributions, which are booted directly from CD/DVD or a USB medium, there are embedded distributions for special hardware, smartphone and tablet distributions, Linux systems for old hardware or for use in educational institutions. If you look at the timeline of Linux distributions, you will notice that Debian GNU/Linux and Slackware are among the oldest Linux distributions. Both systems were first released in 1993 and both distributions have several successors. Debian GNU/Linux is a distribution developed by many volunteers and forms the basis for UCS.
Some Linux distributions are being developed and maintained by companies who offer professional support in addition to the software. Other systems are being developed by volunteers, so-called community distributions. Some enterprise Linux systems cost money, some are free of charge. Univention offers the UCS core edition with a full range of functions for free. It doesn’t matter if you’re just testing the system or using it in a company – an offer that thousands of users gladly accept.
Especially in larger companies or organizations, administrators are requesting professional services. Have a look at our three subscription models if you’re interested in support, in extended maintenance for older UCS versions or additional features.
So, what is a Linux Derivative?
The term comes from the Latin word “derivare” (“to derive, to divert”). A Linux derivative is therefore a fork from another Linux distribution. UCS and UCS@school are both Debian derivates which means they’re based on the community distribution. In fact, we work closely together with the Debian project. Some of our developers are also Debian developers. As a result, you as a customer and we mutually benefit from our work – very much in the sense of Open Source.
Weitere lohnenswerte Artikel zum Thema Linux:
- Linux Programs in Windows: Just Integrate UCS in Active Directory
- How UCS synchronizes Linux/Windows IT Infrastructures with Samba AD
- Linux and Windows Backups: Bareos in the Univention App Center | Part 1