Using uu packer, we can achieve 6bits text encoding in specific case - Compression in Golf: Part I/Uuencoding

see also

• Base64 - binary-to-text encoding schemes that represent binary data in sequences of 24 bits that can be represented by four 6-bit Base64 digits.
  • encode64(bin) - The encode64 method is simply this: [bin].pack("m")
• Why did base64 win against uuencode?