Dragging the shutter
Have you ever taken a photo at night and it looks like it was taken in a cave? No matter how much you adjust your flash your image always comes out the same, bright faces and black everywhere else.
Well the problem is that your flash is only able to illuminate the things that are close which in most cases is the people in your photo, but it can't illuminate the background enough without blowing out the things that are closer. So you have to outsmart your lighting situation by turning your flash down just a little and slowing your shutter speed to capture all of that background light.
This trick is called "dragging the shutter" and what it refers to is leaving the shutter open longer to allow more ambient light to be captured in your image. If you do this correctly your subjects will show up as always and all of a sudden there will be a background to your photo! All you have to do is hold the camera steady so that the background lighting doesn't smear while the shutter is open.
The fastest way to do this is to aim your camera at the background and adjust your settings to capture the background without a flash. (You have to do this on manual or you are wasting your time) Then set your flash to a low setting such as 1/64 or even 1/128 and that will be the little puff of light that will expose and freeze your subjects in the photo. Next take the photo and be sure to hold the camera steady!
Hopefully your photo now shows your subjects and the background. From here you can adjust your flash up or down depending on how your subjects turned out and you can also adjust your shutter speed if you need to depending on how much background you really want to see in your image.
Dragging the shutter is an easy trick and it can even get you some cool motion blur images if you happen to catch people or things that are moving in your photos. You can also experiment with your flash by triggering it at different times durring the exposure or even from different angles.