Just today I realized that Battlestar Galactica isn't Stargate SG-1. What other long-held, easily resolved misconceptions have you had?

I am a sci-fi fan and only today realized these were two different series. All this time I've thought that I hated BSG when really I hated Stargate SG-1 (no offense, Stargate fans). I discovered this by starting the first episode (really, the first part of the miniseries) of BSG on Netflix. Also, Google exists, so I suppose I could have looked there...So far, I deeply regret not figuring this out sooner.