Reverse parking is the only parking method taught in the UK (and thus the only one you're tested on).

The reason you should use this (unless the car park is setup for forward parking bays) is that it's far, far safer.

Forward parking means you need to exit by reversing, functionally blindly, into traffic or children walking across the rear of your car.

Reverse parking means, when you exit, you can see cars wanting to be past, or children now walking across the front of your car.

And no, you're not "trading" safety by reverse parking because, when you park, any obstacles would be directly behind you, as opposed to at an angle.