OpenSUSE

The openSUSE () Project is a worldwide effort that promotes the use of Free and Open Source Software (FOSS) wherever possible.
openSUSE is well known for its Linux distributions, mainly "Tumbleweed", a tested rolling release, and "Leap", a distribution with long-term support. MicroOS and Kubic are new transactional, self-contained distributions for use as desktop or container runtime.
The initial release of the community project was a beta version of SUSE Linux 10.0. The current stable fixed release is openSUSE Leap 15.2. 
Additionally the project creates a variety of tools, such as YaST, Open Build Service, openQA, Snapper, Machinery, Portus, KIWI and OSEM, working together in an open, transparent and friendly manner as part of the worldwide Free and Open Source Software community.
Overview.
The openSUSE Project community, sponsored by SUSE, ARM, B1-Systems, Tuxedo Computers and others, develops and maintains various distributions based on Linux. 
Beyond the distributions and tools, the openSUSE Project provides a web portal for community involvement. The community develops openSUSE collaboratively with its corporate sponsors through the Open Build Service, openQA, writing documentation, designing artwork, fostering discussions on open mailing lists and in Internet Relay Chat channels, and improving the openSUSE site through its wiki interface. openSUSE offers Leap, an LTS-style distribution that shares the code base SUSE Linux Enterprise (SLE), effectively making Leap a non-commercial version of its enterprise-grade operating system. Users that prefer more up-to-date free software can use its rolling release distribution Tumbleweed. Users can also use the Open Build Service. Moreover, the flexibility of openSUSE makes it easy to re-purpose for specific goals like running a web- or mail server.
Like most Linux distributions, openSUSE includes both a default graphical user interface (GUI) and a command line interface option. Users of openSUSE may choose several desktops environments GUIs like GNOME, KDE, Cinnamon, MATE, LXQt, Xfce. openSUSE supports thousands of software packages across the full range of free software / open source development.
The operating system is compatible with a wide variety of hardware on numerous instruction sets including ARM-based single-board computers. Examples include the Raspberry Pi 3 and Pine64 on the ARMv8 platform also known as aarch64, the Banana Pi and BeagleBoard on the ARMv7 instruction set, and the first iteration of the Raspberry Pi on the ARMv6 ISA. RISC-V, PowerPC (PPC64 and PPC64le) and S390 are supported as well.
History of the openSUSE Project.
The first indication that there should be a community-based Linux distribution called OpenSuSE goes back to a mail of August 3, 2005, in which at the same time the launch of the website opensuse.org was announced. This page was available a few days later. One day later the launch of the community project was officially announced.
Discussions about the correct spelling (OpenSUSE, OPENSUSE, OpenSuSE ...) started early, meanwhile openSUSE is widely accepted as the correct spelling.
According to its own understanding, openSUSE is a community that propagates the use of Linux and free software wherever possible. Beside a Linux based distribution it develops tools like Open Build Service, openQA, Kiwi, YaST, OSEM etc, and wants to have fun with it. Collaboration is open to everyone, and even attempts to poach people have had no noticeable effect so far.
Organization.
The project is self-organized without a legal structure, although the establishment of a foundation has been under consideration for some time.
SUSE as the main sponsor exerts some influence, but the project is legally independent of SUSE. openSUSE is a "do-ocracy" in which those, who do the work, also decide what happens (those who decide). This primarily refers to desktop and application development, as the sources of the base packages have been coming from SLE since the switch to the Leap development model. To further unify the base, the 'Closing-the-Leap-Gap' project has been started, where openSUSE Leap 15.3 will be completely based on SLE's binary packages.
Organizational units.
There are three main organizational units:
Product history.
In the past, the SUSE Linux company had focused on releasing the SUSE Linux Personal and SUSE Linux Professional box sets which included extensive printed documentation that was available for sale in retail stores. The company's ability to sell an open source product was largely due to the closed-source development process used. Although SUSE Linux had always been free software product licensed with the GNU General Public License (GNU GPL), it was only freely possible to retrieve the source code of the next release 2 months after it was ready for purchase. SUSE Linux' strategy was to create a technically superior Linux distribution with the large number of employed engineers, that would make users willing to pay for their distribution in retail stores.
Since the acquisition by Novell in 2003 and with the advent of openSUSE, this has been reversed: starting with version 9.2, an unsupported one-DVD ISO image of SUSE Professional was made available for download. The FTP server continues to operate and has the advantage of "streamlined" installs, permitting the user to download only the packages the user feels they need. The ISO has the advantages of an easy install package, the ability to operate even if the user's network card does not work "out of the box", and less experience needed (i.e., an inexperienced Linux user may not know whether or not to install a certain package, and the ISO offers several preselected sets of packages).
The initial stable release from the openSUSE Project, SUSE Linux 10.0, was available for download just before the retail release of SUSE Linux 10.0. In addition, Novell discontinued the Personal version, renaming the Professional version to simply "SUSE Linux", and repricing "SUSE Linux" to about the same as the old Personal version. In 2006 with version 10.2, the SUSE Linux distribution was officially renamed to openSUSE, as it is pronounced similarly to “"open source"”. Until version 13.2, stable fixed releases with separate maintenance streams from SLE were the project's main offering. From late 2015, openSUSE has been split into two main offerings, Leap, the more conservative fixed release Leap distribution based on SLE, and Tumbleweed, the rolling release distribution focused on integrating the latest stable packages from upstream projects.
Over the years, SuSE Linux has gone from a status of a distribution with restrictive, delayed publications (2 months of waiting for those who had not bought the box, without ISOs available, but installation available via FTP) and a closed development model to a free distribution model with immediate and freely availability for all and transparent and open development.
On April 27, 2011, Attachmate completed its acquisition of Novell. Attachmate split Novell into two autonomous business units, Novell and SUSE. Attachmate made no changes to the relationship between SUSE (formerly Novell) and the openSUSE project. After the 2014 merger of the Attachmate Group with Micro Focus, SUSE reaffirmed their commitment to openSUSE.
EQT Partners announced their intent to acquire SUSE on July 2, 2018. There are no expected changes in the relationship between SUSE and openSUSE. This acquisition is the third acquisition of SUSE Linux since the founding of the openSUSE Project and closed on March 15, 2019.
Current Distributions.
openSUSE Tumbleweed.
"Tumbleweed" is the flagship of the openSUSE Project. A stable and tested "Rolling Release", which receives new software each day, and which is basically unbreakable: if a fault occurs as a result of system updates, a snapshot function allows users to revert to a previous system state. Tumbleweed is preferred by openSUSE users as a desktop system.
In the old development model, with each new openSUSE release (13.0, 13.1...) a new rolling release was set-up, which always received new packages. When the new release was at the doorstep, and Tumbleweed was reset to that release, most packages were newer than the ones in the release, which led to problems.
With the switch to Leap, the development model was changed completely: according to the "Factory First" policy all software packages had to be sent to Factory in the first place, before they could be included in a distribution. Out of Factory a daily snapshot is taken and tested in openQA. A successful test is released as the next Tumbleweed snapshot. Unlike other rolling release distributions, Tumbleweed is a "tested rolling release", which increases stability dramatically.
Technically Tumbleweed is the basis for MicroOS and Kubic.
openSUSE Leap.
Leap is a classic stable distribution approach, one release each year and in between security and bugfixes. This makes Leap very attractive as server operating system, but as well for Desktops since it requires little maintenance effort. Online release upgrades are mostly so unspectacular and trouble-free that the community already proposed, the next release should be called 'boring'.
For the version released in the fall of 2015, the development team settled on the name "openSUSE Leap" with the deviating version number 42.1. As in the openSUSE version 4.2 from May 1996, which was called S.u.S.E. Linux at the time, the number 42 refers to the question about "life, the universe and everything" in the Hitchhiker's Guide to the Galaxy book series. After that, the basis packages are received from the SUSE Linux Enterprise, while applications and desktops come from Tumbleweed.
At the openSUSE conference held in Nuremberg in 2016, statistics were announced that since the conceptual reorientation with openSUSE Leap 42.1, increasing user numbers had been recorded. According to this, the number of downloads is 400,000 DVD-images per month with an increasing tendency. Each month, 1,600 installations would be added, and 500,000 packages would be installed. The number of "Tumbleweed" users is 60,000, half of whom frequently perform updates. Thus, the number of "Tumbleweed" installations had doubled in the last year.
Other findings from the statistics are that most installations are done via DVD images. The dominant architecture is x64. The geographical distribution of users has hardly changed according to these figures. One third of users are from Germany, 12% are found in the USA, 5% in Russia and 3% in Brazil.
For the upcoming openSUSE Leap 15.3 release, the repository for openSUSE Leap and SUSE Linux Enterprise (SLE) will be merged and containing the same source code and binary packages. SLE 15 will be supported until 31 July 2028 
openSUSE MicroOS.
MicroOS is a minimalistic, self-maintained and transactional system, which is primarily, but not exclusively, intended for use in edge computing or as container runtime. Some even use it as desktop system.
MicroOS takes a completely new approach to address the needs of Edge- or Cloud-computing: It minimizes the need for maintenance by running from a read-only file system, which prevents accidental changes as well as malware attacks. 
The system is self-contained and transactional, which means that it updates itself in an all-or-nothing approach (transactional) and rolls back to its previous stage in case something goes wrong. The transactional update does not affect the running system. 
Basically all software available for Tumbleweed is also available for MicroOS. As it comes with podman Container-Runtime, MicroOS is the perfect Container-Host. 
MicroOS Desktop is the focus for the 2021 Hackweek
openSUSE Kubic.
Kubic is a Container-as-a-Service Platform, based on MicroOS. It comes with Kubernetes and is designed for large container environments. The openSUSE Community maintains a number of containers in their registry 
The configuration was originally done with Salt, but later it was switched to Kubeadm. Kubic shares the codebase with Tumbleweed and MicroOS and thus allows transactional updates
Features.
YaST Control Center.
SUSE includes an installation and administration program called YaST ("Yet another Setup Tool") which handles hard disk partitioning, system setup, RPM package management, online updates, network and firewall configuration, user administration and more in an integrated interface. In more recent times, many more YaST modules have been added, including one for Bluetooth support. It also controls all software applications. SaX2 was once integrated into YaST to change monitor settings, however with openSUSE 11.3 SaX2 has been removed.
The GTK user interface was removed starting with Leap 42.1, however the ncurses and Qt interfaces remain.
AutoYaST.
AutoYaST is part of YaST2 and is used for automatic installation. The configuration is stored in an XML file and the installation happens without user interaction.
WebYaST.
WebYaST is a web interface version of YaST. It can configure settings and updates of the openSUSE machine it is running on. It can also shutdown and check the status of the host.
ZYpp package management.
ZYpp (or libzypp) is a Linux software management engine. ZYpp is the backend for zypper, the default command line package management tool for openSUSE.
Build Service.
The Open Build Service provides software developers with a tool to compile, release and publish their software for many distributions, including Mandriva, Ubuntu, Fedora, and Debian. It typically simplifies the packaging process, so developers can more easily package a single program for many distributions, and many openSUSE releases, making more packages available to users regardless of what distribution version they use. It is published under the GNU GPLv2+.
Default use of Delta RPM.
By default, OpenSUSE uses Delta RPMs when updating an installation. A Delta RPM contains the difference between an old and new version of a package. This means that only the changes between the installed package and the new one, are downloaded. This reduces bandwidth consumption and update time, which is especially important on slow Internet connections.
Desktop innovation.
KDE.
SUSE was a leading contributor to the KDE project for many years. SUSE's contributions in this area have been very wide-ranging, and affecting many parts of KDE such as kdelibs and KDEBase, Kontact, and kdenetwork. Other notable projects include: "KNetworkManager" – a front-end to NetworkManager and "Kickoff" – a new K menu for KDE Plasma Desktop.
From openSUSE Leap 42.1 to 15.0, the default Plasma 5 desktop for openSUSE used the traditional cascading "Application Menu" in place of the upstream default "Kickoff"-like "Application Launcher" menu. The openSUSE Leap KDE experience is built on long term support versions of KDE Plasma, starting with openSUSE Leap 42.2. With openSUSE Leap 15.1, the Plasma 5 desktop now again defaults to the "Kickoff"-style application menu.
GNOME.
The Ximian group became part of Novell, and in turn made and continued several contributions to GNOME with applications such as F-Spot, Evolution and Banshee.
The GNOME desktop used the "slab" instead of the classic double-panelled GNOME menu bars from openSUSE 10.2 to openSUSE 11.4. In openSUSE 12.1 "slab" was replaced with the upstream GNOME Shell and GNOME Fallback designs.
Starting with openSUSE Leap 15.0, GNOME on Wayland is offered as the default GNOME session. GNOME Classic, GNOME on Xorg, and "GNOME SLE" are offered as alternative sessions to the more upstream Wayland-based session.
Factory & Tumbleweed.
The Factory project is the rolling development code base for openSUSE Tumbleweed, a Linux distribution. Factory is mainly used as an internal term for openSUSE's distribution developers, and the target project for all contributions to openSUSE's main code base. There is a constant flow of packages going into Factory. There is no freeze; therefore, the Factory repository is not guaranteed to be fully stable and is not intended to be used by humans.
The core system packages receive automated testing via openQA. When automated testing is completed and the repository is in a consistent state, the repository is synced to the download mirrors and published as openSUSE Tumbleweed, which many developers and hackers from the openSUSE Project use as their primary operating system.
Releases.
From 2009 to 2014, the openSUSE project aimed to release a new version every eight months. Prior to the Leap series, versions 11.2-13.2 were provided with critical updates for two releases plus two months, which resulted in an expected support lifetime of 18 months.
Starting with version Leap 42.1 (after version 13.2), each major release is expected to be supported for at least 36 months, until the next major version is available (e.g. 42.1, 15.0), aligned with SUSE Linux Enterprise Releases. Each minor release (e.g. 42.1, 42.2, etc.) is expected to be released annually, aligned with SUSE Linux Enterprise Service Packs, and users are expected to upgrade to the latest minor release within 6 months of its availability, leading to an expected support lifecycle of 18 months as well. Tumbleweed is updated on a rolling basis, and requires no upgrades beyond the regular installation of small updates and snapshots.
Evergreen was a community effort to prolong maintenance of selected openSUSE versions after they reached official end-of-life before the Leap series.
Reception.
Jesse Smith from DistroWatch Weekly reviewed openSUSE Leap 15.0, lauding the "work that has gone into the system installer", simplify for new users, but criticized the lack of media support, and performance issues, like a slow startup or slow shutdown.