Ubuntu is a Debian-based Linux operating system and distribution for personal computers, smartphones and network servers. It uses Unity as its default user interface. It is based on free open source software and named after the Southern African philosophy of ubuntu (literally, 'human-ness'), which Canonical Ltd suggests can be loosely translated as "humanity to others" or "I am what I am because of who we all are". Development of Ubuntu is led by UK-based Canonical Ltd, a company of South African entrepreneur Mark Shuttleworth.