Uuencode (Uuencode/Uudecode)

Uuencode (also called Uuencode/Uudecode) is a popular utility for encoding and decoding files exchanged between users or systems in a network. It originated for use between users of UNIX systems (its name stood for "UNIX-to-UNIX encoding"). However, it's available or easily obtainable for use in all operating systems and most e-mail applications provide it as an encoding alternative, especially for e-mail attachments. If you're sending e-mail with an attachment and you suspect your recipient(s) may not have a MIME-compliant system (for example, an older PC or UNIX system), you may want to specify "Uuencode" for the attachment to an e-mail note. (In Eudora, when writing a note, look for the little box set to a default of "MIME" and change it to "Uuencode.")

Basically, what Uuencode does is to translate or convert a file or e-mail attachment (it can be an image, a text file, or a program) from its binary or bit-stream representation into the 7-bit ASCII set of text characters. Text can be handled by older systems that may not handle binary files well and larger files can be more easily divided into multi-part transmissions.

If your recipent is likely to be on an older Macintosh system, you may want to try sending the attachment in another format called BinHex.

A popular program for encoding and decoding files in Uuencode format is WinZip, which is shareware that you can download from the Winzip Web site.

This was last updated in January 2006

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