Mirror writing is created by writing in reverse direction, so that it is the reflection or mirror image of normal writing. Mirror writing is a simple form of cipher. It is commonly used on emergency vehicles, such that an important identifier, such as “AMBULANCE,” can be read in the correct order in a driver’s rear-view mirror. Leonardo da Vinci used mirror writing for personal notes. Mirror writing calligraphy was popular in the Ottoman Empire, where it often carried mystical associations. Mirror writing is associated with senility and brain disorders. The earliest printing presses used reversed type cut into wood blocks and later lead blocks.