Dalek writing
From Tardis Wiki, the free Doctor Who reference
The Daleks had a form of writing.
Overview
During the 22nd century invasion of Earth, the Daleks placed notices around London locations with uncertain meaning. (TV: The Dalek Invasion of Earth)
Dalek writing was displayed both on screens and in the vision of certain Dalek factions. (TV: Remembrance of the Daleks)