Eclipse

Releases

Since 2006, the Eclipse Foundation has coordinated an annual Simultaneous Release. Each release includes the Eclipse Platform as well as a number of other Eclipse projects. Until the Galileo release, releases were named after the moons of the solar system.

So far, each Simultaneous Release has occurred at the end of June.

Release         Date             Platform version    Projects
Indigo          June 2011        3.7                 Indigo projects
Helios          23 June 2010     3.6                 Helios projects
Galileo         24 June 2009     3.5                 Galileo projects
Ganymede        25 June 2008     3.4                 Ganymede projects
Europa          29 June 2007     3.3                 Europa projects
Callisto        30 June 2006     3.2                 Callisto projects
Eclipse 3.1     28 June 2005     3.1  
Eclipse 3.0     28 June 2004     3.0  

To summarize, Helios, Galileo, Ganymede, etc are just code names for versions of the Eclipse platform (personally, I'd prefer Eclipse to use traditional version numbers instead of code names, it would make things clearer and easier)