Encoding and Encryption

Encoding

Encoding means converting of data from one form to another. It has several types including image encoding, audio and video encoding and character encoding.

By encoding digital audio, video and image files into different, more efficient, compressed formats a lot of disk space can be saved. Encoded media files typically maintain similar quality to their original uncompressed counterparts but have comparatively smaller file sizes. A WAVE (.wav) audio file that has been converted to an MP3 (.mp3) file may be 1/10th the size of the original WAVE file. This also applies to the MPEG (.mpg) compressed video file which takes only a fraction of the disk space the original digital video (.dv) file would take.

Encoded data can only be read by a program that supports that type of encoding. This is accomplished by Codecs in the case of audio and video files, which decodes the data in real-time.

Encryption

Encryption is used to code or scramble the meaning of messages. These messages can then be decrypted only by someone who has the correct code or key, which is called a cipher. Encryptions are primarily used to secure web sites or any other means of data transfer. If a third party were to intercept a message sent via a secure connection, they would be unable to make any sense of the encrypted data.

The use of encrypted messages dates back thousands of years to the Romans, who first used substitution ciphers. The first machines to use ciphers came into use during the 1930’s. The German Enigma cipher machine which was used during World War II used multiple rotors to create a continuously varying cipher that was thought to be unbreakable. Allied code breakers succeeded in exploiting the flaws of the German machine with electro-mechanical and electronic devices, while simultaneously unknowingly advancing computing technology.