Tomorrow, January 15th, is the 15th anniversary of the launch of Wikipedia.
Wikipedia was my very first taste of the Wiki crowd-editing platform designed by Ward Cunningham. Wikipedia was such a disrupting force in education that teachers I had at the time were specifically telling us not to use Wikipedia as a jumping off point for anything because it couldn't be trusted (common argument: Anybody can write anything they want!). Their fears didn't quite turn out that way though as Wikipedia quickly turned into a treasure trove of trusted information with links to plenty of primary sources on all sorts of topics. Sure, Wikipedia still falls victim to malicious attacks and jokes here and there, but it's come a long way from being a hated misinformation source to a beloved website with a neverending trail of links.
The web's changed a lot in 15 years and Wikipedia has grown with it, becoming much more than any bound paper copy of an encyclopedia could ever be or contain. Check out all the milestones for Wikipedia here.