Cryptography is a technique used for encrypting (in our point of view) files. A file could be anything; from a simple ASCII text to a complicated zipped file or an executable. There are numerous algorithms used to encrypt a file and they are practically unlimited methods to achieve this.
Hackman comes with an encryption algorithm with its undo, the decryption of the encrypted file.
Every encryption method requires a password. ItÆs a unique for every file or bunch of files sequence of Ascii characters (case-sensitive for us) which is used by the algorithm to produce a new file that has nothing in common with the original except of a mathematical sequence that helps us to go from one side to the other.