Anonymous 101: a wired.com writer "embeds" with Occupy and Anonymous and gives a decent primer in three parts
so... some criticize wired.com but any source will have its shortcomings and if you need to get up to speed on Anonymous, this is a good place to start. it's a three part series (only two parts done so far), it's comprehensive, so you may want to bookmark it and come back to it later for the other two parts.
think 21 century yippies, merry pranksters, this sort of thing, for the digital age. it's good stuff, and they have a lot more in store for us in 2012.