Putting your
arms around another person as a show of
affection. While some people might consider a hug
intimate, most don't, depending on the type of hug. It usually
signals that you
care for the person, with the amount of
caring demonstrated by the
intensity of a hug.
Girls love to hug, but guys, on average, aren't as into them - however, there are exceptions to this, and those guys that do love hugs are a wonderful thing. Most guys, though, tend to do either the "bear hug", overdoing it a bit, or doing the "pat on the back" thing that somehow makes it less offensive to masculinity or something like that.