One of the strengths (and, arguably, one of the weaknesses) of the English language is the variety of words and phrases it offers to communicate the same thought. Such a breadth of choice has allowed subtle nuanced differences in meaning and tone to be associated with such terms over time, creating a richer, fuller language that is capable of more powerful and precise expression. Such includes the case of the greeting, a situation with many available selections for the speaker.
“Hello.”
This is the classic default, a fairly neutral English-language greeting with little inherent flavor. While it can be made into an excited-to-see-you message, given as an exclamation, overall it denotes a polite pleasantry; informal enough for use with anyone, but not quite as laid-back as a one-syllable sound or a non-verbal cue. Variants include the more pointed “Hello there,” which can even be turned into the bemused, curious or surprised “Well hello there.”
“Hi.”
Likely a shortened version of “Hello” that was filed down over time, this is a slightly more familiar, relaxed English-language greeting. While an introduction may follow in the case of meeting a new person to make it a little more official, it is typically used between friends and casual acquaintances. This is a greeting of minimal pomp and effort, usually cast aside in favor of an actual topic of conversation.
“What’s up?”
This phrase has gone through interesting progressions in its cultural effect, even within relatively recent history. It is a lighthearted, carefree greeting, a remnant of such two-word usages as “What’s happenin’?” or “What’s going on?” An exaggerated variant was used for a popular Super Bowl commercial, in which the sound is humorously drawn out over a cell phone call. Otherwise, although this greeting implies a question, the phrase often is not a literal request for more information, rather a polite formality, to such an extent that those who actually respond by explaining what is up may be seen as odd or trying to be ironic.
“Greetings.”
As generic as this one-word English-language greeting is, seeming to serve to merely describe itself in a self-referential or meta sense, it is actually typically taken as a step above the previous options in terms of possessing a hint of more occasion and formal etiquette. Then again, perhaps just as often, the somewhat official sounding is used just as much to be funny. Drawing out the two syllables emphasizes its formality, and overall, it is not a dreadfully popular or often-heard greeting.
“Hey.”
Now we have a greeting that is so casually informal that it can even border on impolite or taken as rude, depending on context. Perhaps because of, when delivered even slightly forcefully, the shoved-forward nature of the actual physical formation of the word, it holds more of a more push-away implication than other greeting options. This is especially true when not even bothering with a person’s name, such as with “Hey you!” Using the person’s name will, at least, offer a sense of secure familiarity; although, one vogue usage is to keep the name off, but in use with a close friend or relative, thus making this a light, sarcastic cue of playful teasing.
“Yo.”
Whether it merely derived as a shortening of the term “hello,” or a simple phonetic arbitrarily basic resort, some people carry this greeting with a northeastern American distinction, such as with a thick Brooklyn accent poured on for good measure. Whatever its origin, this is a simple, lighthearted, quick greeting, that also sees some dual use as an attention-getting call.
“How are you?”
Similar to “what’s up?” in the sense that it is not always a literal question, this one is more often meant that way, as a genuine asking of how the other person is doing. But when some people cut right to using this query as a greeting, the inquisitive aspect is usually dropped and meant purely as a greeting. This is an English-language greeting that serves as the likelier candidate when a reunion takes place after a notable length of time, as the two parties seek to catch up with each other and make up for the absence.
“Good day.”
This popular English-language greeting has many variants, depending on the time of day, just as with other Romantic languages such as Spanish. For example, “good morning” and “good afternoon” see use before and after noontime, respectively. In addition, “good evening” will see use, while “good night” and “goodbye” are used for departure instead.
“Top o’ the mornin’ to ya.”
Though this is a traditional Irish greeting, noted for its inherent positive wish upon the recipient, it certainly qualifies as an English-language greeting. It is certainly not overwhelmingly popular, but along with some heritage use it may also spike in frequency around St. Patrick’s Day.
“What’s the word?”
Maybe more so than with any other of the prior English-language greetings, this is one that stands on personal preference over any form of trend or popularity. One variant is “What’s the good word?” and, in either form, this is a greeting that a person may choose to use as their greeting of choice. It is certainly a distinctive choice, capable of throwing the recipient off-guard if they are unready for such a unique option. Like other question-type greeting, the question is rhetorical, and even more so than the other query-based greetings, an attempt to answer will most likely make the respondent sound ridiculous as they try to form a coherent, relevant reply.