An alternative to conventional punctuation which specifies the placement of periods, commas, and exclamation marks outside of quotation marks when they do not belong in the quote.

For example:
     If he told you, "Eat a mammal", then you should.
as opposed to:
     If he told you, "Eat a mammal," then you should.

The driving force of this reform probably comes from the proliferation of etext, especially in the form of email. As a new medium for information exchange that differs significantly from print, electronic writers are developing new conventions to replace those that no longer work. In the case of quotes, because of the spacing of computer text, quotation marks hover far from the actual quote and look rather silly and may even convey false information.

For example:
   Mail me! My username is "J1TN-23."
where the period is not part of the person's username.

In addition, logical punctuation resembles the way a computer programmer would separate strings of text; a comma appears outside the quotes because it separates the strings but is not part of any string. Hence the "logical" aspect.