* Old English: The closest ancestor of "hello" is "hál" meaning "whole" or "healthy." It was used in greetings like "hál be þú" (be whole/healthy to you).
* Middle English: This transitioned to "hale" and "hail" used in greetings like "hail fellow well met."
* 19th Century: The modern "hello" started appearing in the 19th century, likely as a shortened and more casual form of "halloo" (a call used for getting attention).
So, while there's no single inventor, the evolution of the word "hello" reflects the changing language and customs over centuries.