o, n.All

What did O say to Q?Is that a gun or are you just pleased to see me?

O is the oldest letter of the alphabet, dating back to 3000 B.C

The "O" before an Irish name (ex O'keefe, O'Reilly, etc) means "descendant of."

What did the letter O say to Q?Dude, your junk is hanging out.

O is the blue vowel.