Uses 91 characters, and every pair of characters represents either 13 or 14 bits. Since 2^13 < 91*91 < 2^14, two characters can encode all 13-bit strings and some 14-bit strings; since 91*91=8281 and 2^13=8192, there are 89 combinations of two characters that are not used for representing strings of 13 characters. The particular choice is: for a string of 14 bits, if its lowest 13 represent a number greater than or equal to 89, the two characters are used to represent only these 13 bits; otherwise, 14 bits are encoded.
reviving 'ascii armor' concept
ASCII armor was apparently the original title of this article. It is now 'binary to text encoding'. The ascii armoring concept consists of more than just encoding binary into ascii, it also consists of encoding plain text for purposes of archival or transmission. Therefore, it should go back into the article. drefty.mac 17:33, 27 October 2006 (UTC)
Base26 should be kept
- I apologize. At first glance it looked kind of spammy. Feel free to add it again, but use a citation format instead of a direct URL as a source. And please add a citation for the other two entries. —EncMstr (talk) 03:47, 12 September 2013 (UTC)
It makes little sense to include a term 'efficiency' in the table, if there is not any kind of explanation or mentioning of what it is. Someone would probably want to add this information. - 184.108.40.206 (talk) 18:11, 19 March 2015 (UTC)