Facebook is a social networking website founded in 2004 by Mark Zuckerberg and his Harvard classmates. It allows users to connect with friends and family from around the world. Facebook has grown rapidly since its founding and now has over 800 million active users. The site allows users to create profiles, share photos and videos, join groups, and connect through messages and newsfeeds. While free to use, Facebook's primary features also come with risks like oversharing personal information, addiction, and fake profiles.