Yes, CFDs are designed to take advantage of price movements in both directions.
So, can you short cfds? In short, no pun intended, yes you can – they are designed to take advantage in changes in the price of underlying assets no matter which direction they are going (though you must of course decide beforehand whether you think the price is going up or down – long or short, and trade accordingly).
Going ‘short’ on a CFD (contract for difference) can be very useful if you believe that the price of an underlying asset is going to drop. Say, for example, that you believe that economic conditions will lead to the price of an underlying share to decrease, then this is the perfect opportunity to use a CFD to go short and capture this price drop as profit. Mechanically, going short on a CFD is done as making a sell order on the CFD, and then later closing out that position when the price has dropped.
Though over large timeframes (ie decades), in general, most assets such as share indexes have increased in value, on a day to day basis price fluctuations can be wild, and involve regular ups and downs. So, if you limit yourself to only long positions, you are effectively missing out on a large proportion of possible profit, or from gaining any time the price of an asset drops. Also, typically in markets such as the share market, it’s said that “the market goes up the stairs and down out the window” meaning often that gains are slow, but that sharp drops in price can happen very quickly (hence the analogy of up the stairs, and falling to the ground out the window). This is particularly attractive to experienced CFD speculators as large price changes over short time periods offer a real opportunity to use Contracts for Difference profitably. As such, in consideration of the above, I would urge you to consider shorting CFDs as a possible strategy to add to your CFD (contract for difference) arsenal.