Here's a good example of how to do an info-dump right without it being a "dump":
Have you read Brave New World? Do you know the very first scene, where the new workers are touring the hatchery and the director is telling them how everything works? You get a lot of information in a very "As you know, Bob" way...but it works, because these are new workers, who don't know, and it makes sense that they're being instructed. Plus, it's interspersed with other scenes in which we are introduced to all kinds of other new concepts without any exposition about what they are. If you the director had been talking to another worker who already knew how it all worked, it would feel very fake, and it would be an "As you know, Bob" infodump.
And of course, infodumps don't have to be in dialogue. It can be in the exposition, where--just as the two lovers are introduced--the writer randomly starts explaining in detail how they met and started dating, etc., when either a) it doesn't really matter or b) it does matter, but not yet, and it belongs elsewhere. (For some reason, in my summer class, just about every writer who had a couple in their story did this...)