When MariaDB was first announced in 2009 by Michael "Monty" Widenius, it was positioned as a "fork of MySQL". I think that was a Bad Idea™. Okay, maybe it wasn't a bad idea as such. After all, MariaDB indeed is a fork of MySQL. But what is a fork in the software sense, and how is this reflected in MariaDB? A fork is a software project that takes...