It also has a neat kind of crowd-sourced verification attached to it.
If someone asks a question, and someone else gives an incorrect answer, chances are good that someone will see that and correct them. If, on the other hand, everyone goes and looks up the answer, some people might get an incorrect answer and have no one to correct it, further disseminating false information.
Obviously this isn't perfect, and requires that the information is fact-based in the first place, but it's interesting to think about any time you see someone correct someone else on the internet.