IdMessageCoderUUE.pas contains classes and methods used to implement coders and decoders for RFC 2822-compliant message parts using the UUEncode encoding/decoding algorithms. 

The UUEncode algorithm is designed to encode binary data into a 7-bit textual representation, called UUEncode, as established in UUCP (Unix-to-Unix Copy Program). 

UUEncode, like Base64, is an encoding mechanism designed to represent arbitrary sequences of byte data in a form that need not be humanly readable. UUEncode is often used to send EMail attachments in an environment that is not MIME-compliant, and also allows larger files to be divided into multi-part transmissions.