What is encrypte?

Answer 1

Encoding of data to prevent unauthorized access to data or to be more descriptive:

Encryption refers to algorithmic schemes that encode plain text into non-readable form or cyphertext, providing privacy. The receiver of the encrypted text uses a "key" to decrypt the message, returning it to its original plain text form. The key is the trigger mechanism to the algorithm.
Encryption is any of several methods of concealing the message content from prying eyes. A Crypt is a hidden place.

This does not apply just to the written word, one can conceal within a photo some secret identifying features, invisible or meaningless to the casual person who may wish to copy your intellectual property.