uuencode

UUencode is a command line tool used for encoding binary files and data into a format that can be safely transmitted over email or other text-based communication channels. It was developed as part of the Unix-to-Unix Copy (UUCP) protocol and is widely supported by various Unix-like operating systems.

The UUencode command takes a file or standard input as input and produces a text representation of the data as output. This encoded output is comprised of only printable ASCII characters, ensuring compatibility with different platforms and communication channels.

UUencode uses a simple algorithm to convert each three bytes of binary data into four characters. It splits the data into 6-bit chunks, adds 32 to each chunk to convert it into a printable character, and finally appends a newline character after every 60 characters.

The encoded output can be easily copied and pasted into an email or text file. To decode the encoded data, the UUdecode command is used, which understands the UUencoded format and reconstructs the original binary data.

UUencode also supports additional features, such as file and directory permissions preservation, specifying the name of the encoded file, and specifying the mode (permissions) for the decoded file.

While UUencode is primarily used for email transmission, it can also be used for other purposes, such as saving binary files as text files or embedding binary data within source code files.

UUencode is considered a simple and efficient method of encoding binary data into a text format, though it has been largely replaced by more modern encoding schemes, such as Base64. However, it remains available on many Unix-like systems and can still be useful in certain situations.