Vampire is a role-playing game in which the players take on the role of vampires in the modern world (Masquerade) or the medieval one (Dark Ages). Various supernatural entities exist, and their struggles take place in the shadows. Vampires, in particular, take care to not be noticed by humans, as they are vulnerable during the day. In the Dark Ages, this is a crude and brutal “Silence.” In the modern days, this requires a more delicate and subtle “Masquerade.”
There are six main versions of Vampire. Four for Masquerade (1st, 2nd, Revised, and 20th Anniversary) and three for Dark Ages (Vampire:Dark Ages, Dark Ages: Vampire, and Dark Ages 20th Anniversary), with an official 5th on its way. There’s not a huge difference between the editions (though I talk about some of them here), and I tend to mix them all together. All in all, any such differences are slight, and more a matter of preference.