In 1989, a Finnish student called Linus Torvalds started an improvement work of Minix's Kernel, an operational system like Unix wrote by Andrew Tannenbaum, calling his own Kernel as Linux, a mix of Linus and Minix.
The main idea about this new Kernel is that it's free. Anyone can develop to improve the Kernel, share the software, change it specific application and distribute without any fee or restriction. All the code is open.
Finally, in 1991, Linus launched the first official Linux version, later joining Richard Stallman's GNU project in 1992 with the objective to produce the complete operational system that we know today.
Linux had fast success on the x86 architecture and soon it had ported for various processor architectures and became very popular on embedded devices in many different applications like automotive, industrial, telecommunications, consumer and internet appliances.
The use of Linux in embedded devices has many advantages:
There are many distributions of Linux available for free. Below are a list of some of them:
Ubuntu (IPA: [uːˈbuːntuː] in English,[ùbúntú] in Zulu) is an operating system for desktops, laptops, and servers. It has consistently been rated among the most popular of the many Linux distributions. Ubuntu's goals include providing an up-to-date yet stable Linux distribution for the average user and having a strong focus on usability and ease of installation. It is a derivative of Debian, another popular distribution. Ubuntu is sponsored by Canonical Ltd, owned by South African entrepreneur Mark Shuttleworth. The name of the distribution comes from the African concept of ubuntu which may be rendered roughly as "humanity toward others", "we are people because of other people", or "I am who I am because of who we all are", though other meanings have been suggested. This Linux distribution is named as such to bring the spirit of the philosophy to the software world. Ubuntu is free software and can be shared by any number of users.
Kubuntu and Xubuntu are official subprojects of the Ubuntu project, aiming to bring the KDE and Xfce desktop environments, respectively, to the Ubuntu core (by default Ubuntu uses GNOME for its desktop environment). Edubuntu is an official subproject designed for school environments, and should be equally suitable for children to use at home. Gobuntu is an official subproject that is aimed at adhering strictly to the Free Software Foundation's Four Freedoms. The newest official subproject is JeOS. Ubuntu JeOS (pronounced "Juice") is a concept for what an operating system should look like in the context of a virtual appliance.
Ubuntu releases new versions every six months, and supports those releases for 18 months with daily security fixes and patches to critical bugs. LTS (Long Term Support) releases, which occur every two years, are supported for 3 years for desktops and 5 years for servers. The most recent LTS version, Ubuntu 10.04 LTS (Lucid Lynx), was released on 29 April 2010. The current non-LTS version is 10.10 (Maverick Meerkat) released on 10/10/10 (10 October 2010).
Mandriva Linux (formerly Mandrakelinux or Mandrake Linux) is a Linux distribution created by Mandriva (formerly Mandrakesoft). It uses the RPM Package Manager. The product lifetime of Mandriva Linux releases is 18 months for base updates and 12 months for desktop updates.
openSUSE, (pronounced /ˌoʊpɛnˈsuːzə/), is a community project, sponsored by Novell and AMD, to develop and maintain a general purpose Linux distribution. After acquiring SUSE Linux in January 2004, Novell decided to release the SUSE Linux Professional product as a 100% open source project, involving the community in the development process. The initial release was a beta version of SUSE Linux 10.0, and as of October 2007 the current stable release is openSUSE 10.3.
Beyond the distribution, openSUSE provides a web portal for community involvement. The community assists in developing openSUSE collaboratively with representatives from Novell by contributing code through the open Build Service, writing documentation, designing artwork, fostering discussion on open mailing lists and in Internet Relay Chat channels, and improving the openSUSE site through its wiki interface. Novell markets openSUSE as the best, easiest distribution for all users.
Like most distributions it includes both a default graphical user interface (GUI) and a command line interface option; it allows the user (during installation) to select which GUI they are comfortable with (either KDE, GNOME or XFCE), and supports thousands of software packages across the full range of open source development.
Fedora is an RPM-based, general purpose Linux distribution, developed by the community-supported Fedora Project and sponsored by Red Hat. Fedora's mission statement is: "Fedora is about the rapid progress of Free and Open Source software."
One of Fedora's main objectives is not only to contain free and open source software, but also to be on the leading edge of such technologies. Also, developers in Fedora prefer to make upstream changes instead of applying fixes specifically for Fedora – this ensures that updates are available to all Linux distributions.
Debian (pronounced [ˈdɛbiən]) is a computer operating system (OS) composed entirely of software which is both free and open source (FOSS). Its primary form, Debian GNU/Linux, is a popular and influential Linux distribution. It is a multipurpose OS; it can be used as a desktop or server operating system.
Debian is known for strict adherence to the Unix and free software philosophies. Debian is also known for its abundance of options — the current release includes over twenty-six thousand software packages for eleven computer architectures. These architectures range from the Intel/AMD 32-bit/64-bit architectures commonly found in personal computers to the ARM architecture commonly found in embedded systems and the IBM eServer zSeries mainframes. Throughout Debian's lifetime, other distributions have taken it as a basis to develop their own, including: Ubuntu, MEPIS, Dreamlinux, Damn Small Linux, Xandros, Knoppix, Linspire, sidux, Kanotix, and LinEx among others. A university's study concluded that Debian's 283 million source code lines would cost 10 billion USA Dollars to develop by proprietary means.
Prominent features of Debian are its APT package management system, its strict policies regarding its packages and the quality of its releases. These practices afford easy upgrades between releases and easy automated installation and removal of packages. Debian uses an open development and testing process. It is developed by volunteers from around the world and supported by donations through SPI, a non-profit umbrella organization for various free software projects.
The default install provides popular programs such as: OpenOffice, Iceweasel (a rebranding of Firefox), Evolution mail, CD/DVD writing programs, music and video players, image viewers and editors, and PDF viewers. Only the first CD/DVD is necessary for the default install; the remaining discs contain all 26,000+ extra programs and packages currently available. If a user does not wish to download the CDs/DVDs, these extras can be downloaded and installed separately using the package manager. Debian can also be configured to download and install updates automatically.
Slackware is a Linux distribution created by Patrick Volkerding of Slackware Linux, Inc. Slackware was one of the earliest distributions, and is the oldest currently being maintained. Slackware aims for design stability and simplicity, and to be the most Unix-like GNU/Linux distribution.