There are many styles of hugs. Some are good, some are bad, and some should really be eliminated. I'm even guilty of most of them, but I think it's time for a change.
As it were, here's a brief description of some hugs.
This is the hug that may as well have never happened. One (or both) of the people involved puts their hands on the other's shoulders and leans forward just enough to brush heads briefly. The feeling left from it is so faint you might forget within seconds that it even occurred. Else, you'll obsess over why you bothered in the first place, like I do. Women are usually guilty of this type of hugging. It can convey one of two messages. It either says, "I don't know you and I'm afraid you're a psycho, so don't touch me again," or, "I don't really like you, but I'm trying to be polite."
I also call this "the skinny hug", and thank you, I'd rather shake hands.
Also known as the guy hug, the pat hug has got to be one of the worst, most useless and superficial gestures on the planet. The parties toss their upper halves forward, reach around, and pat each other on the back. No other physical contact is involved. Between men, it's usually intended to say "Hey, I like you, but I'm not homosexual." I suppose it can be useful if your friends are homophobes, but let's get real. If anyone is worried that a little body contact will make one gay, they shouldn't be touching at all.
Sometimes guys give the pat hug to women, too. In those cases, it's saying the same thing as the "scared hug". Please, I've had better hugs from wind gusts and dead people. Okay, maybe not dead people.
Women use the pat hug to "console" their targets. It's not as sympathetic as one might think, though. It really means, "Stop crying/whining. I have stuff to do."
Bear hugs are great if they're done right. Some particularly strong people can squeeze the air right out of your lungs. That's bad. A good bear hug consists of full body contact and a complete, firm hold around the person. A slight squeeze is often presented, as well, though one should be cautioned against the aforementioned stealing of breath. Between men and women, it's not uncommon for the man to pick the woman up and sometimes swing her around. Again, caution is advised. You don't want to break her back.
If done correctly and between real friends, bear hugs say, "It's really great to see/be with you!"
Sexy hugs, like bear hugs, involve full body contact. There are two main differences, however. In the sexy hug, there is rarely any squeezing, and no one is getting picked up (well, not literally). One party lightly wraps him/herself around the other and presses some private part into them. Slight wiggling motions of said private parts might also occur. The sexy hug says, "I think you're hot. Let's have wild monkey sex."
Advisory! Do not attempt the sexy hug if you aren't absolutely positive the other person will like it/is interested! To do so makes it a bad hug!
The real consoling hug is not the same as the woman's version of the pat hug. It involves, at the very least, upper body contact, and the hugger will rub, not pat, your back. This is to say, "Go ahead and cry. I'm here for you."
Hugs between lovers
These are really an entirely different matter, and won't be addressed here, but they are often very similar to...
The best hug I ever had
It came from a person I'd only met once before, but I'll never forget it. He really knows how to give a hug. I doubt I can truly convey its impact, but I'll try.
It was a full body hug, but completely unlike bear hugs and sexy hugs. I might have mistaken it for a lover's hug if I didn't know better. He wrapped his arms around me firmly and stood there for what seemed like days (I wouldn't have minded eternity). No patting, no rubbing, just holding me close. We were in a very crowded room, but something about it said that I was the only one there to him. When it was over, I was reeling with happiness and felt like I'd been healed.
What did that hug say to me? "I appreciate you and all that you are. Let's be human together." Wow. What a beautiful thing to say.