Nathan Yau of Flowing Data has a blogpost about the many terms floating around visualization. It’s worth reading! But, in my opinion, not complete without Robert Kosara’s sometimes constrasting view.
Terminology is often flourishing in thriving disciplines where people seek to differentiate themselves and find their niche. It’s probably not that bad, but while potentially adding differentiation it also introduces confusion (as above posts/lists show), especially when talking to people with a slightly different angle.