A blackboard, also called a chalkboard, is a surface on which chalk is visible. It is used as a surface to write on. It is usually made up of wood or fiber. It is painted black to reflect the white chalks.
Blackboards are often used to help in teaching in school. Blackboards are not used as much now but can be seen in some schools still. The chalk dust got everywhere, and some people are allergic to chalk dust. Now people use whiteboards: they can take modern felt-tip colour markers, and clean easily.
Schoolteachers often use the chalkboard to display things at large. It also makes the learning cooperative between teachers and student. Chalkboards can be black or dark green, in which case they may be called blackboards and greenboards.
- Originally, actual geological chalk was used. However, in the 20th century it was an artifical product.