base91x is an advanced method for encoding binary data as ASCII characters. It is similar to UUencode or base64, but is more efficient. The overhead produced by base91x depends on the input data. It amounts at most to 23% (versus 33% for base64) and can range down to 14%, which typically occurs on 0-byte blocks. This makes base91x very useful for transferring larger files over binary insecure connections like e-mail or terminal lines. base91x is a basE91 modifcation to be XML and JSON friendly. Original basE91 can be found here: http://base91.sourceforge.net/