http://www.urbandictionary.com/define.php?term=r&defid=572090
The lazy representation of an inferred response, possibly a ‘default’ response if you will. As such, ‘r’ may frequently be understood to mean:
- Yes
- No
- Correct
- Hello
- Goodbye
- Fine thanks
The word, or letter, may prefix certain textual emoticons, which enhance its meaning.