Mountain Lion's Contacts

"Among the many things your Mac is tasked to do is to help you stay in touch with other people. And the first step in doing so is to have some notion of how to contact them—through email, snail mail, phone, chat, FaceTime, and social networking services. The repository for this vital information is Mountain Lion’s Contacts application. Formerly known as Address Book, Contacts is often overlooked, since many people think that the job it handles is mundane." Mountain Lion's Contacts