The definition of uucode

The point of uucode is to allow 8-bit binary data to be transferred through the more common 7-bit ASCII channels (most especially e-mail). The facilities for dealing with uucoded files exist for many different machine types, and the most common programs are called "uuencode" for encoding the original binary file into a 7-bit file and "uudecode" for restoring the original binary file from the encoded one. Sometimes different uuencode and uudecode programs will work in subtly different manners causing annoying compatibility problems. Bcode was invented to provide the same service as uucode but to maintain a tighter standard.