Today, pencils are everywhere, from schools to golf courses to any art studio. What seemed like a simple invention is now a billion-dollar global industry. But who invented this household staple? 

Before there were pencils, the preferred writing instrument was the stylus, which had been around since the ancient Romans. Some were made of thin pieces of metal that left light marks on a paper-like material called papyrus. Other styluses—which stuck around all the way until the 16th century—were made of lead, which proved to be a harbinger of writing instruments to come.

More modern pencils arose thanks to a bit of luck and some creativity. In 1564, a tree fell down in England and unearthed a large deposit of graphite, an incredibly valuable mineral. Unlike lead, graphite could leave dark gray, almost metallic marks on paper. Despite being made of carbon, many believed it to be lead

According to NPR, a Swiss naturalist named Conrad Gessner created the first depiction of a pencil in 1565. His drawing portrayed graphite inside wood. That illustration became popular throughout Europe, but it wouldn’t be until the 1700s that pencils as we know them started taking shape.

The late 18th century saw further pencil improvements. France, no longer able to trade with England while at war with Britain, became desperate for its own source of graphite. As a substitute, engineer Nicolas-Jacques Conté created the “Crayons Conté.” He mixed cheap graphite with wet clay, which was then sculpted into a rod-like shape and baked. 

Since Conté, many have improved on the pencil, including Henry David Thoreau. Thoreau created pencils that didn’t smudge as much, as well as the numbering system that notes the firmness of the graphite. The rise of factories and machines also helped make the writing instrument more popular. Eberhard Faber opened the first pencil factory in the U.S. in 1861, about 100 years after his family opened their first one in Germany. Hyman Lipman attached the first eraser to a pencil in 1858. He received a patent, but it was later invalidated by the courts, as he didn’t create erasers, just combined two items.