National Hug Day or National Hugging Day is an annual holiday occurring on January 21. The holiday was founded on January 21, 1986 in Caro, Michigan, and has since spread to Canada, England, Australia, Germany and Poland.
A hug is a form of physical intimacy, not necessarily sexual, that usually involves closing or holding the arms around the neck or waist of another person. Hugging has been proven to have health benefits. One study has shown that hugs increase levels of oxytocin, and reduce blood pressure. Hugging is not particular to human beings, as there are many species of animals that engage in similar exchanges of warmth.
In recent years it has become a practice amongst some teenage girls to greet and farewell each other with a hug. In May 2009, the New York Times reported that "the hug has become the favorite social greeting when teenagers meet or part these days" in the United States. A number of schools in the United States have issued bans on hugs, which in some cases have resulted in student-led protests against these bans. (With material from: Wikipedia)