Third Long Term Support (LTS) release of Ubuntu. Released April 2010. It was supported until 9th May, 2013 on Desktops and will be supported until April 2015 on Servers. Codenamed "Lucid Lynx". You should only use this tag if your question is hardware or version-specific.
Other Ubuntu Flavors available under 10.04 LTS:
- Ubuntu Studio
Ubuntu Editions available under 10.04:
Questions about Desktop edition are considered off-topic since it had reached the end of life.