In communication and information processing, encoding is the process by which a source converts information into message data, which is then sent to a receiver (such as a data processing system).
In telecommunication, the term encode has the following meanings:
1. To convert data by the use of a code, frequently one consisting of binary numbers, in such a manner that reconversion to the original form is possible.
2. [To] Convert plain text to equivalent cipher text by means of a code.
3. To append redundant check symbols to a message for the purpose of generating an error detection and correction code.
See also: Character encoding
Source: from Federal Standard 1037C and from MIL-STD-188 and from the National Information Systems Security Glossary