Picocrypt !free! -

You're referring to PicoCrypt, a simple, paper-based cryptographic scheme.

PicoCrypt uses a combination of substitution and transposition ciphers to encrypt messages. The scheme consists of a set of printable tables and grids that are used to transform the plaintext message into ciphertext. picocrypt

Here's an overview:

If you'd like to learn more or try out PicoCrypt, you can find printable materials and documentation online. Would you like some references or resources to get started? You're referring to PicoCrypt