Version 1.0 was released back in 2000

Version 1.2 came in 2001

2002 saw version 2.x arrive

Version 3.0 arrived in 2003

Version 4.0 was released 2004, and 4.1 in 2005

The 5.x series was released between 2006 and 2007

6.0 was released in 2012, and 6.1 in 2015