7th September 2006 marked the start of eighth year for Google. Google was launched on 7th September in 1998. Matt Cutts explains it well. Users of Google must be thinking why Google is celebrating it's birthday on 27th September. Well last year Google did not celebrate its seventh birthday on 7th September because many things were happening on that day. They were able to celebrate only on 27th September. This year probably they did not notice when 7th September came and passed.