ehname

I was trying to think of a good way for answering this, but it's kind of difficult, since the styles under the krautrock umbrella are so diverse. But... if you'd bear with me:

Uninformed people refer to Kraftwerk as being krautrock, which is true to the extent of maybe a couple of their earliest releases (and their previous name Organisation), but since these are not typically the Kraftwerk albums that people know about, the whole krautrock genre gets this electronic/synthy reputation (hence you putting this in the electronic forum originally). There are also people that set the equals between krautrock and what is typically called "kosmisch musik" (cosmic music), which I'd take with a pinch of salt, since most of the krautrock isn't very cosmic. It's true that most of the progressive electronic stuff coming out of, what is refered to as, the Berlin School is cosmic. But these aren't very rocky (again, hence the electronic reference). Bands that belong here are Ash Ra Tempel (later Ashra), Tangerine Dream, Klaus Schulze, some Popol Vuh, and the likes. These are mostly spacey synthscape music, borderlining new age music, so if you come from a Zeppelin/Purple background and don't want to go too offkilter, this might not be for you.

Then there's what modern people nowadays refer to as the "krautrock sound", which is most often basically the sound of the "motorik beat", which is a steady 4/4 monotonuos drumbeat. Bands that belong here are Neu!, La Düsseldorff, to some extent Can (although Jaki Liebezeit has a much jazzier groove), as well as early Kraftwerk, some Harmonia, Cluster, etc. If a modern band today tells you they play krautrock, they will most probably sound like Neu!, and people seems to diffuse the genre name to bands also outside of Germany. This style is hugely overrated, I think.

Now, to the good parts of krautrock!
Although most of the time when people talk about krautrock they refer to one of the two aforementioned styles, the huge part of the krautrock movement don't fit there, imo. These seems to be more underground and less commercially succesful, which is the psych/prog-rock side of the spectrum. Some of the most common names are allready mentioned in this thread (Amon Düül II, Guru Guru, etc, etc), which are all superb. But I'd like to shine some light on some of the more unknown gems that are really great aswell. Try Gäa, Xhol Caravan, Pell Mell, Kickbit Information, Vinegar, Kaputter Hamster, Twenty Sixty Six And Then,... ****, I don't like to post these long lists of recommendations, but these are really all top notch!