Hidden message

A hidden message is information that is not immediately noticeable, and that must be discovered or uncovered and interpreted before it can be known. Hidden messages include backwards audio messages, hidden visual messages and symbolic or cryptic codes such as a crossword or cipher.
Although there are many legitimate examples of hidden messages, many so-called hidden messages are illusory.
More information on the Wikipedia page and linked articles; the Wikipedia page on hidden text is .
See Smithy code
Category:Reference