Fans discuss whether Kramer and Newman have first names, comparing to other TV characters who went by single names like Quincy and Colombo, with jokes about Newman's greeting.
I have seen the string of WHAT IS KRAMMERS first/last name, and IMO I think its rather nice to have a character that goes just by one name, just look at the old jack Klugman(sp?) show QUINCY. As far as I can remember, he went just by QUINCY, QUINC or even DR QUINCY, never a first/last name.
According to 'the complete directory to prime-time network TV shows' 1985 edition, Baratta's name was Dt. Tony Baretta.
According to the same source 'Quincy's first name was never mentioned on the show, he did apparently, have a first initial. His business card was seen briefly in one episode and it read "Dr. R. Quincy."
The same source confirms that Lt. Columbo never had a first name.
(it also states that the part was originally offered to Bing Crosby, who declined it because he was 67 years old and a multi- millionaire. I'd hesitate to post it here except for the connection to the fact that the part of George was offered to Sting and he too declined, saying he didn't want to shave his head :D )