Major/minor revisions
"Surely a primary version number update is when you are breaking compatibility with the previous version. Basically you are saying Program X will work with Version Y.*, but we cannot guarantee that it will work with Version Z.*"
I am not a linux expert but version 2.4 and 2.6 for example changed the kernel API which broke (every?) drivers. It was a surprise and shock and meant I had to port across various drivers. It probaby should not have been a shock but I use lots of different operating systems and what is the point of major and minor versions if you don't use it to indicate compatibility?
Biting the hand that feeds IT
