We started saying ‘hello’ to attract attention on the telephone
Saying hello is now synonymous with greeting someone. It’s a word that, with some necessary spelling changes, is spoken in languages around the world, and at first glance seems appropriate for all kinds of contexts. However, its usage is actually pretty limited, only going back around 150 years. It’s not that people haven’t always greeted each other when they met, but that seeing someone in person wasn’t nearly as alarming as hearing their voice on a telephone.
We take the ability to speak on the phone for granted now, to the point that many of use avoid using a device that was once considered a marvel of modern technology. When it was invented, the phone was a totally new social space for people to make sense of, requiring its own set of etiquette to go with it. Alexander Graham Bell felt that this long-distance communication would make sense borrowing nautical terms for some reason, and always answered the phone with ahoy. Thomas Edison, perhaps noting that ships aren’t known for facilitating direct conversation, pushed the idea of hello, although that word carried a bit more impact in the 19th century than it does today.
Hello’s history as hail
The word hello comes from variations of hail, and as such is closely related to holler. It was used as a greeting, but often in bigger, public declarations than a one-on-one conversation, such as “hail to the king!” By the 1800s, hello’s exclamatory value was central to its usage, and it would be used mostly to show surprise or draw attention to something exciting, such as “Hello! What’s this?!” So Edison’s use of hello on a phone wasn’t really a socially bland greeting as much as a punctuated call for an answer from a distant shore. Aside from ahoy, which wasn’t going over with anyone, hello was actually competing with phrases like “Are you there?”
Hello is now used around the world, but mostly in the context of phone calls, showing how hearing a voice over a wire still occupies a particular space in our brains. Popular alternatives to hello or allo often retain the flavor “are you there.” In Spanish, diga is technically asking if you can be heard on the other end of the line. In Russian, я слушаю is basically saying “I’m listening,” again drawing attention to the fact that you’re in a conversation with someone that can’t see you. As forms of written communication like text messaging occupy larger portions our telecommunications, will hello simply shed this notion of an excited shout through the void, or will it fade away altogether?
Hi and hey
If hello really has peaked, it’s a safe bet that hi will be a replacement. As comfortable as hi feels in a text message or email, it actually has a very similar history to hello. It’s thought to be a variation on hey, which of course could also be shouted to draw attention to something of interest. Nonetheless, hi has brevity on its side, making it an easier word to use when you can already trust their phone to have gotten their attention for you.
Source: Where Does 'Hello' Come From?, Words at Play