Wikipedia has some definitions and some examples of different...

Wikipedia has some definitions and some examples of different trading strategies that might be termed "short" .
Essentially, any strategy that is not purely "long" is "short" in some way (!). Long means paying and holding in the hope of price increase. Strictly, "shorting" stock means selling a stock (that you have not paid for and do not own) in the hope of buying it back at a lower price. End result of either strategy if you are succesful: profit in the hand and no stock held.

There are many ways that you can implement a "short" strategy. Some involve borrowing shares, some involve derivatives.

The term is maligned and misunderstood.

Personally I implement "long" strategies since I do not yet have the time, resources, nerve or experience to tangle with the "dark side" yet. I'm sure I will hold a short position someday when the situation demands it; hedging your long positions that you don't want to sell is an example of that.