From http://www.investorpedia.com a basic definition:
1. A method of hedging a portfolio of stocks against the market risk by short selling stock index futures.
1. This hedging technique is frequently used by institutional investors when the market direction is uncertain or volatile. By short selling index futures they offset any downturns, but they also hinder any gains.
What I get sick of in reading the many blogs out there is the simplistic polarity of either "bulls are dumb", or "bears are evil" depending upon the perspective of the blogger (and boy could I name some names). Lost in the shuffle of bull vs bear argument is that enough unusual things are happening from subprime collapse to Iran nukes is that you can't go wrong with hedging or buying portfolio insurance to protect yourself.