Chalk Board

We all must have seen what a chalk board is for those who have never seen one a chalk board is a reusable writing surface that can be written upon by a piece of calcium sulfate or commonly known as chalk. The purpose of the chalk board is as a writing instrument in colleges, classes, in meeting rooms, etc. The advantage of using a chalkboard is that you can write and erase from a chalk board as many times as possible without wasting any writing materials except chalk.