The Matoran alphabet is similar to the English alphabet, being a simple substitution cipher. In Mata Nui and Metru Nui, the letters and numbers are circular symbols. On Voya Nui and a secret laboratory on Bara Magna, these symbols are hexagon-shaped, but are otherwise identical, except for "K", which was identical at first, but was later changed to the rotated "Y" shape that it now has.