According to the Oxford English Dictionary, hello is an alteration of hallo, hollo, which came from Old High German "halâ, holâ, emphatic imperative of halôn, holôn to fetch, used especially in hailing a ferryman." It also connects the development of hello to the influence of an earlier form, holla, whose origin is in the French holà (roughly, 'whoa there!', from French là 'there'). As in addition to hello, halloo, hallo, hollo, hullo and (rarely) hillo also exist as variants or related words, the word can be spelt using any of all five vowels
"Goodbye" came from the Middle English "godbwdye", which is short for "God be with ye."
"Goodbye" came from the Middle English "godbwdye", which is short for "God be with ye."
Hello, Goodbye - The Beatles