linux.conf.au (often abbreviated as lca) is Australasia's regional Linux and Open Source conference. It is a roaming conference, held in a different city every year, coordinated by Linux Australia and organised by local volunteers.
The conference is a non-profit event, with any surplus funds being used to seed the following year's conference and to support the Australian Linux and open source communities. The name is the conference's URL, using the uncommon second-level domain .conf.au, just as other conferences - such as FOSS.IN - now do.
The conference is one of three major, international, grass-roots open-source conferences world wide. The other two are the Linux Symposium (commonly known as OLS) and Linux Kongress.
Read more about Linux.conf.au: Conference History, Miniconfs