The two most popular mechanisms of message encryption are now shift encryption and basic encryption. In presentation encryption, the order of characters in a given text is changed, keeping all of them unchanged, but in an unidentifiable order.

In the second type of encryption, the characters change with respect to the assumed formula. To begin with, a few definitions: ciphertext - encrypted message; plain text - original message without encryption; sliding encryption - a cipher consisting in shifting letters in the alphabet by fixed X positions; symmetric encryption - encryption and reading of information is based on the same key; asymmetric encryption - encryption and information reading are processes using other keys; cryptography - learning about data security, including encryption; cryptography - a science that examines encryption mechanisms and assesses how secure they are in the event of a breach attempt. public key and private key - keys occurring in asymmetric codes; the public key is used to encrypt messages and the private key allows them to be read on the device to which the ciphertext has been sent; steganography - the technique of including hidden information in plain text.

Popular encryption algorithms: DES - a very popular symmetric encryption system used, among others, by public institutions in the United States; RSA - an asymmetric algorithm based on first numbers; it is commonly used, including public data transfer, file encryption and digital signature authentication; DSA - an algorithm most commonly used in digital signatures; MD5 - an unusual algorithm used for one-way encryption and not allowing to read the plain text; it is used primarily for authentication, because the logging data entered are converted into a string of data, which is then compared with the original string, so that without knowing the content of the message, its authenticity can be verified.