Что такое доска?

«Доска» имеет много значений, в том числе, но не ограничивается:

Это поверхность для письма, обычно изготавливается из белого металлического пластинчатого материала, который можно стирать и писать повторно. Обычно используется для обучения, meeting discussions or personal and family notes. It is similar to a blackboard and must be written with a special whiteboard pen.
It is an Internet slang that refers to the state of knowing almost nothing about a certain technology.
In mahjong, white boards refer to tiles that do not have words or patterns engraved on them.
In some dialects, it has a derogatory meaning, and is usually used to express a person’s dissatisfaction with others, or to describe stupidity and uselessness.
In addition, «blank slate» is also a philosophical term used by the British philosopher Locke.