Every year, on March 30, National Pencil Day celebrates the man who first put an eraser at the back end of a pencil.

Back in the 1700s and 1800s pencils and erasers were always separate, until Hymen Lipman changed that. On this March 30, 1858 Lipman got his first patent for the pencil with an eraser attached at one end. He did this to make things like writing and drawing easier and a bit less tedious.

According to the National Day Calendar, pencils weren’t yellow until around the 1890s. It all started because one company wanted to make the best pencil ever and wanted to distinguish itself by making the pencil yellow, but other brands started to copy them because they wanted their pencils to be seen as high quality as well.

Have you ever wondered how pencils are made? It’s really very simple. The part that actually writes, the graphite, is made by combining graphite, clay, and water and then put into a cylindrical mold. It is put into a kiln so it can harden. After it’s hardened, the graphite is inserted and glued into the pieces of wood that encase it, that have already been designed with a hollow groove. Then the pencil is cut it and designed on the outside. The manufacturer can choose the add erasers, which is standard on graphite pencils although not on colored pencils.

Perhaps the best way to really celebrate this holiday is to buy pencils and use them for their intended use, drawing or writing.