"Pure" ASCII would be 7-bit US-ASCII derived directly from the teletypewriter command set. It consists of exactly 128 character codes, of which roughly 30% are

"Pure" ASCII would be 7-bit US-ASCII derived directly from the teletypewriter command set. It consists of exactly 128 character codes, of which roughly 30% are unprintable. Anything beyond that, such as code page 437, are not "pure". It should also be noted that the first 128 character codes of UTF-8 are "pure" 7-bit US-ASCII...