Many space cover collectors also collect astronaut/cosmonaut signatures on space covers, photographs or other items. A major problem with collecting signatures is telling the difference between authentic signatures and autopen signatures. The later use to be produced by a special machine but these have largely been replaced by a computer and plotter. Another problem is fakes which seem to be more prevalent today than in the past. This section of the Space Unit Web site will be devoted to showing examples of authentic and autopen signatures of various astronauts/cosmonauts as well as links to useful sites on the Internet and books on the topic.