Ubuntu is 1) the 'brand' name of a version of Linux for the desktop that is easy to use, 2) a relational concept derived from the Bantu language of South Africa' 3), the name of the World Forum of Civil Society Networks
Ubuntu as software
Wikipedia article at http://en.wikipedia.org/wiki/Ubuntu_%28Linux_distribution%29
“a free, user-friendly operating system that combines Linux with a word processor, Web browser, spreadsheet application and PDF reader. The software is distributed by CD, upgraded every six months, and is easy for ordinary computer users to install.”
“Mark Shuttleworth, an entrepreneur from Cape Town, South Africa, is the driving force behind Ubuntu . Shuttleworth sold his digital-security company for $500 million, and since 2004 has spent $25 million in developing and distributing Ubuntu to the people of the world. His goal is to distribute localized versions of Ubuntu to dozens of countries where people cannot afford (or even acquire) proprietary software in their own language. “There are some 350 languages in the world with more than a million speakers,” Shuttleworth told The Economist (June 7, 2007). “Free software is only translated in a significant way into about 20 of those, although this is already a lot greater penetrating than proprietary software.” (http://onthecommons.org/node/1171)
Status Report 2007
David Bollier at http://onthecommons.org/node/1171
“More than six million CDs with Ubuntu have been distributed already. While diffusion is still in its early stages, momentum is growing. Just this month, the French Parliament switched its computers to Ubuntu. Dell, the computer maker, offers computers pre-loaded with the system, and makes money by selling technical support and service for the software. Michael Dell says he has Ubuntu on his personal computer.
Ubuntu represents the next, more mature stage in the evolution of free/open source software. The project is not about bashing proprietary software, but about building better software and sharing communities on a global scale. What’s fascinating is how efficient the Ubuntu commons has been. For a fraction of the advertising budget for Microsoft’s new Vista operating system, Ubuntu is reaching millions of people with free, high-quality software that gives them greater user freedoms -- and this viral growth is likely to expand.
Ubuntu is also likely to seed a new generation of innovators who in time could out-perform Americans locked into the culture of proprietary software. As Linux becomes the standard platform for the next generation of tech innovation, it could also begin to dissolve proprietary technical barriers that currently make various portable devises incompatible. A new interoperability via Linux could unleash powerful new rounds of bottom-up innovation.” (http://onthecommons.org/node/1171)
The relationship between Ubuntu and Debian
"Ubuntu is explicitly based on Debian, but this doesn't come without its problems. From the beginning Canonical, Ubuntu's holding company, employed a core of key Debian Developers. This created some jealousy among Debian Developers and some annoyance that energies were being diverted away from the Debian project. These irritations were compounded by a perception that the Ubuntu developers were not feeding back their changes, and that Canonical's own software projects such as Launchpad, were not being released under free software licenses. These issues came to a head at Debconf in 2006, when Shuttleworth and Ubuntu team members met with Debian Developers to discuss their concerns, and it was agreed that greater acknowledgement would be given to the Debian contribution to Ubuntu and to promote better communication between the two projects.
Ubuntu is unlike other Debian derivatives which, for the most part, have been based on the stable release and are less intimately involved with the Debian development process. As Steve McIntyre, the British developer who was recently elected to be Debian Leader for a second one-year term, observes: "Ubuntu is undoubtedly the most popular of all the spin-offs, and has the highest profile. They also tend to have the widest target audience(s) of all the derived distros; many of the others are focussed on smaller groups of users, e.g. specialised for netbooks or educational users. Ubuntu is also one of the few members of the Debian family that itself is commonly used as a base for further derivations."
Resolving the issues is as much a concern for Canonical as it is for the Debian developers. Despite a spate of misplaced headlines claiming that Ubuntu is bigger than Debian, Ubuntu needs Debian to maintain its momentum and is dependent on the good faith of the Debian Developers." (http://www.h-online.com/open/Health-Check-Ubuntu-and-Debian-s-special-relationship--/features/113260/1)
More articles on this topic:
- Conflicting goals create tension in communities - Mark Shuttleworth
Ubuntu as relational concept
= "Ubuntu derives from Bantu, a southern African language, and relates to a Zulu concept - umuntu ngumuntu ngabantu - which means "a person is only a person through other people". 
"Ubuntu: An African word (and proverb) meaning "I am human because you are human." Ubuntu psychology says, "Sharing ourselves and our gifts with others optimizes our collective and individual humanity. Even in the sharing and the giving, the individual or "other" group receives the gifts and the glories of humanity." (http://ubuntupsychology.blogspot.com/2010/06/ubuntu-african-word-and-proverb-meaning.html)
Ubuntu ... essence of being human...the fact that my humanity is caught up and is inextricably bound up in yours. A person with ubuntu is welcoming, hospitable, warm and generous, willing to share...open and available to others, affirming of others; do (sic) not feel threatened that others are able and good, for they have a proper self-assurance that comes from knowing that they belong in a greater whole and are diminished when others are humiliatedor diminished.
- Desmond Tutu 
""The concept of Ubuntu has recently received a lot of attention in spite of the fact that there is no consensus about its meaning. African scholars have strived to attain a common meaning and English translation, and while they agree that it is typically and solely African, the closest some have come up with is 'African humanism'. A South African saying is frequently used to illustrate the core tenet of the ethics of Ubuntu: 'unumtu ngumumntu ngabantu', which translated into English means: 'A person depends on others to be a person.' The principles underlying the way of life proposed by Ubuntu are transferred from generation to generation through fables, sayings, proverbs and by tradition through the socialization of children in which the whole community is involved. Bearing in mind that traditional values may become diluted or lost during times of change and urbanization..." (http://ubuntupsychology.blogspot.com/2010/05/childrens-understanding-of-ubuntu.html)
More information in the Wikipedia at http://en.wikipedia.org/wiki/Ubuntu_(philosophy)
Ubuntu in Zulu means, - “I am because you are”
Ubuntu as an organisation
See: World Forum of Civil Society Networks, http://www.ubuntu.upc.edu/
- Ubuntu Code of Conduct = sets the community norms for the Ubuntu Free Software community. 
- Ubuntu - Governance
Listen or Watch:
- Mark Shuttleworth on Ubuntu: Interview by Open Business focuses on the Business Ecology of
- Mark Shuttleworth on the Business Ecology of Ubuntu
- Mark Shuttleworth on the Roots of Ubuntu
- Jono Bacon on Community Management at Ubuntu: "Interview with Jono Bacon, Community Manager for Ubuntu, at the 2009 Linux Foundation Collaboration Summit in San Francisco."