Some abilities of Vampires are extremely long life. They can turn others into vampires, but it's not contagious, as they choose who to turn and tend to be quite selective.
Some weaknesses are that they are unable to go into the sunlight and can't change from human to vampire and vise versa. However, modern books like Twilight and others, make vampires seem more human, but with different abilities , unusually keen senses, and a much slower rate of aging.
Of course, capabilities and weaknesses vary among different types (Nosferatu, living vampires, et cetera). Some are only moderately affected by garlic, preferring to avoid it. Some cannot be exposed to sunlight, some can handle indirect exposure; living vampires tend to continue their lives much as before they were carried across, as they can still be exposed to direct sunlight, but might be more photo-sensitive. Odds are, even if you met a living vampire, or any type of vampire, for that matter, you would not realise it unless he/she admitted it to you, but that is highly unlikely, as most prefer to retain their anonymity.