Terminology question re ASCII

Quick question on terminology use concerning a legacy encoding:

If one refers to "plain ASCII," or "plain ASCII text" or "... characters," should this be taken strictly as referring to the 7-bit basic characters, or might it encompass characters that might appear in an 8-bit character set (per the so-called "extended ASCII")?

I've always used the term "ASCII" in the 7-bit, 128 character sense, and modifying it with "plain" seems to reinforce that sense. (Although "plain text" in my understanding actually refers to lack of formatting.)

Reason for asking is encountering a reference to "plain ASCII" describing text that clearly (by presence of accented characters) would be 8-bit.

The context is one of many situations where in attaching a document to an email, it is advisable to include an unformatted text version of the document in the body of the email. Never mind that the latter is probably in UTF-8 anyway(?) - the issue here is the terminology.

TIA for any feedback.

Don Osborn

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Received on Mon Oct 28 2013 - 23:15:57 CDT