Difference between Joomla 1.5 Joomla 1.6 and joomla 1.7? [closed]

Question

What is the difference in versions of Joomla CMS i.e. Joomla 1.5, Joomla 1.6 and joomla 1.7 ?

Answer 1

Main Differences between 1.5 and 1.6

Refined Access Control Layer One-click upgrades of core CMS

J1.6 to 1.7 is very much an incremental upgrade - lots of small refinements to user workflow.

J1.8 will be called J2.5 - but don't ask why.