I was watching Touch the other day...
"It's a cypher!"
"What's a cypher?"
"A cypher is a machine that makes codes."
The writers/producers think that their audience is so pigignorant that they did not know what a cypher was, or that they couldn't have worked out what a cypher was form the context of the story?
Who hasn't among us explained the story of the Enigma Code to their children while polishing off the washing up?
Water finds it's own level.