Modern usage is from the use of the telephone hence French say allò as a telephone greeting but Bonjour normally. However, I know that Spanish has the greeting 'Hola' which is not related to the use of the telephone and I wonder if this is connected to the earlier origin and not the later, in which case, at what point did the Spanish start using Hola as a greeting and did it coincide with the British usage? Questions, questions!
This however is not the main reason I'm posting. The Etymology site comes with this nice quote from Fowler to accompany 'hello':
I'm English and I can't remember the last time I saw anyone write hullo in either a letter, email or modern literature. Do any of you from the British Isles still use it?"Hello, formerly an Americanism, is now nearly as common as hullo in Britain (Say who you are; do not just say 'hello' is the warning given in our telephone directories) and the Englishman cannot be expected to give up the right to say hello if he likes it better than his native hullo. [H.W. Fowler, "A Dictionary of Modern English Usage," 1926]