The process of taking the credit card number, encrypting it, and storing it in a token database. In return there is a token to take its place. The concept of tokenization is to use a non-decryptable piece of data to represent, by reference, sensitive or secret data. In payment card industry (PCI) context, tokens are used to reference cardholder data that is stored in a separate database, application or off-site secure facility. When using tokenization the credit card token has no bearing on the actual credit card number. The token is a reference to where the number is stored within the token database, like the dewy decimal system in a library.