A bulletin board is a surface intended for the posting of public messages, such as to advertise items for sale, announce events, or provide information. Bulletin boards are often made of cork to facilitate the addition and removal of messages, and they can also have a writing surface such as a blackboard or whiteboard. There are also combination bulletin boards that have both a pinboard and writing surface. Bulletin boards can be found in various settings such as dormitory corridors, well-trafficked hallways, classrooms, lobbies, home offices, kitchens, and kids rooms. They are particularly prevalent at universities and are used by many sports groups, extracurricular groups, and anything from local shops to official notices. Bulletin boards can also be entirely in the digital domain and placed on computer networks so people can leave and erase messages for other people to read and see, as in a bulletin board system.

In summary, a bulletin board is a surface for displaying notices that give information about something, and it can be made of cork or a combination of cork and a writing surface. Bulletin boards can be found in various settings, and they can be physical or digital.