Encode binary?

Base 64 or quadrosexagesimal is a positional notation using a base of 64. It is the largest power-of-two base that can be represented using only printable ASCII characters. This has led to its use as a transfer encoding for e-mail among other things. All well-known variants that are known by the name Base64 use the characters A–Z, a–z, and 0–9 in that order for the first 62 digits but the symbols chosen for the last two digits vary considerably between different systems. Several other encoding methods such as uuencode and later versions of binhex use a different set of 64 characters to represent 6 binary digits, but these are never called by the name Base64.