How do you say “hi” to that person you’re really happy to see? You can wave, pound fists or flash a big smile and just say something like, “Wow, it is so great to see you!” But in this day and age, only one thing really does the moment justice, capturing the full range of happy sentiments in one action: a hug.

Do you like hugs? Yes, you do. You shouldn’t even have to think about the question, because biology suggests that we humans are programmed to love hugs. The sensation of touch is a fundamental part of our animal instincts, and studies show that hugs may also boost the release of oxytocin, our “cuddle hormone.” Even if you think you don’t like hugs, if you find hugging to be a useless and pointless ritual, chances are your hormones say otherwise.

Still, it’s one thing to enjoy a hug from a close friend, family member or significant other. It’s another thing to want to hug every random person you come across on campus. But that’s the way things are developing–there are hugs everywhere and from almost everyone, whether you like it or not. From Free Hug campaigns to hugs from colleagues who are not quite your friends, less-than-intimate hugging is here to stay.

And while you don’t have to seek out a free hug from a hippie holding a cardboard sign, the eternally complicated question remains: When are you metaphorically close enough to someone to warrant a hug?

The strangest hug of all, in my opinion, is the goodbye hug after the first meeting with a stranger. You’ve been emailing this stranger for a week, and finally the two of you meet in a coffee shop or cafe to talk about something vaguely professional. This person is definitely not your peer, but he or she is only a few years older than you, so you get along quite well. Soon enough, it is time to say goodbye.

So, is it time for a hug? Answers may vary, but my experience has shown that the hug is the unofficially proper way to end that type of interaction. But the person was a stranger! Ah yes, a stranger an hour ago. After that hour, you two must celebrate the fact that you managed to get along by hugging.

The unique thing about hugging is that once someone goes in for the hug, you can’t back away: The intent to hug is binding. How many times has a proffered hug completely caught you off guard? “Oh, I didn’t know we were hugging friends…” you think to yourself as you extend your arms stiffly in return and close your eyes to make the moments pass by more quickly. Or perhaps, in a moment of unbridled enthusiasm, you open yourself up for a hug only to have the other person tentatively do the same, barely brush you and recoil as if you were diseased.

Then there are the hugs that, even if mutual, just don’t feel right. Because hugs mean different things to different people, styles may clash. For some people, a “hug” just means a simultaneous pat on the back. Serious huggers prefer the full-body, two-arm, front-to-front hug, while others go for a one-arm, side-to-side hug that is more like a mutual lean than a true embrace. Of equal consideration are hug duration and hug movement: Some huggers want to hold onto you for about 30 seconds longer than you anticipated. Some huggers want to sway from side to side while holding onto you. In this brave new world of hugging, we have no choice but to acclimate to others’ quirks.

Is hugging on the rise? We may be hugging more because we’re comfortable being uninhibited in our biological instincts or, maybe, because everybody else is doing it. A 2009 article in The New York Times observed the growing phenomenon at the high school level, in which many teenagers’ most common greeting had suddenly become the hug.  Now, in 2012, many of those teenagers are college students. This means that hugging, like knowledge of the Backstreet Boys, is moving up the generational ladder.

This suggests that the race to embrace will only continue in the future. Even as I type, thousands of college students accustomed to hugging are moving into the professional realm. Are you and your professors on hugging terms? Not yet. Do you hug your boss? It may happen soon. It’s time for us to get used to hugs, for they will only continue to bring us closer together.

Want to give Miriam a hug? Send her an email at melloram “at” stanford “dot” edu.