It was written in the rongorongo script, carved in wood. Unfortunately, the language has not been deciphered to this day because a large portion of the community was abducted by Peruvian slave traders, some who could read died, and those who remained could not read.
In 1914, researcher Katherine Routledge came across a man who could read rongorongo writing. He was staying in a leper home. She reached out to him, but he refused to reveal the secret of the writing to a stranger. It is believed that he left his students on the island because the ability to write and read was passed down from generation to generation.
Research into deciphering the writing is still being conducted.