The first real blackboard was invented by Scottish educator James Pilland. He was the principal of the old Edinburgh High School and taught geography using a blackboard and colored chalks he invented. It has the function of repeated erasing.
In 1801, George Barron, a mathematics teacher at West Point Military Academy, became the first American to use a large blackboard for class. But the first blackboard patent was registered more than twenty years later by American educator Samuel Hall, who painted a pine board black. At the same time, some people painted lime, plaster of paris and pot smoke directly on the classroom walls.
Water-ground glass in the 1990s, current color-coated steel plates, composite material plates, etc. are used as blackboard materials.
Nowadays, the types of blackboards include blackboards, green boards, and whiteboards in terms of color; flat panels and curved panels in terms of surface shape; and bracket movable panels and push-pull panels in terms of structural composition. Lifting boards and magnetic blackboards are divided into teaching blackboards, office whiteboards, advertising boards, display boards... and teaching blackboards include electronic blackboards, multifunctional combination boards, interactive electronic whiteboards, projection boards with screens, etc.