Craigslist is a classified advertisements website that was originally created as a San Francisco community newsletter. It allows users to post classified ads for jobs, housing, items for sale, and other services in their local communities. Craigslist has expanded to over 450 city-specific sites worldwide while keeping operations small. It generates revenue through fees for job and apartment listings in major cities but remains non-commercial otherwise. One challenge is preventing scams, like buyers overpaying for items and then not receiving them.