The new Build Center adopts the term distribution to replace the previous term installation - or what was casually referred to as a "box". The term distribution comes from software distribution, which refers to a collection of software components that are configured to work together. We have chosen this term because it describes the output that Extension developers build in the Build Center more accurately. The hope is that by changing to a term that is well understood in the developer communities, there will be less confusion and lower learning curve for Extension developers.
A distribution still contains one or more versions. One big difference is in how the settings are split between a distribution and its versions. The distribution holds all settings that are shared among its versions, such as name, permission, and so on. A version contains distinct information specific to itself such as the inheritance setting, builds, first aids, and so on.