Here is the trivia word for the day. The term "nickname" originated as an Anglo-Saxon word: ekename. In the Anglo-Saxon tongue, "eke" meant "also" or "added." The term seemed just a bit awkward to pronounce; so, it became slurred, converting ekename to nekename and finally to become nickname.
The idea of a nickname didn't come from English origins, though. They were originally common in ancient Greece and Rome, especially when used as terms of affection, which the Greeks called hupokorisma, meaning "calling by an endearing name."
It was not uncommon for English parents to give their children long names and abbreviate them for ordinary use, which they called "nurse names" - so Harold became Hal and Elizabeth became Betsy.
Of course, children and adults often get tagged with somewhat less endearing names. Lefty, Shorty, Pinky and many others were probably not earned in the nursery.