Short selling can take the following forms:Selling physical...

Short selling can take the following forms:

Selling physical shares that you don't own through a stockbroker - he will "borrow" the stock. You cannot short a stock when the "borrowing" capability is not avaialble.You cannot short sell every stock on the ASX.

Selling CFD's - this is probably simpler than the first example but effectively gives you the same result.Also a product where you can use leverage.

Sell call options/buy put options.

Problem with all of these is that it is not a zero sum gain. Unless you have strict risk parameters set when you enter a short position you can easily lose more than you put in quite simply because a stock could go much higher than your entry price for a number of reasons as opposed to only going to zero on the downside.