Dalek writing

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The Daleks had a form of writing.

Overview

During the 22nd century invasion of Earth, the Daleks made notices around London locations with uncertain meaning. (DW: The Dalek Invasion of Earth)

Post-Last Great Time War Dalek markings

All Daleks from a post-Last Great Time War era had markings below the eyepiece.

While the exact purpose of these marking is unknown, they may be either a form of identification or rank insignia.

There are also markings of this type on the incinerator into which Cpt. J. Harkness is thrown on the Crucible. (DW: The Stolen Earth/Journey's End)