A bulletin board is a flat surface, usually made of cork or fabric, where people post notices, announcements, and messages for others to see. You'll find bulletin boards in schools displaying student artwork, upcoming events, or lunch menus. Libraries use them to advertise reading programs and community activities. Offices post work schedules and important reminders.

The beauty of a bulletin board is that it creates a shared space for information. Instead of telling each person individually about the science fair, a teacher can pin one colorful poster where everyone will see it. Students might tack up flyers for their club meetings or lost-and-found notices. Some families keep bulletin boards at home for grocery lists, appointment reminders, or photos.

People attach items to bulletin boards using thumbtacks (small pins with flat tops) or pushpins. The cork or fabric surface holds the pins securely, but lets you remove and rearrange items easily.

The term can also describe online forums where people post messages and replies, like a digital version of the physical board. These electronic bulletin boards work the same way: they're public spaces where anyone can read what's posted and add their own contributions to the conversation.