Motion blur: motion blur can be an important feature in a work because it can show the viewers eye to focus on one specific part of the photo. The 9th photo in this slideshow shows the motion blur the best because it is intentional. It blurs the scarf she is swinging while keeping other parts of the photo in focus. If the subject is too bright you would change the ISO of the camera.
These photos are composed with artificial light. The key and fill lights were used mostly, and i never used a back lit photo. Most of these photos are very bright. but you could have a very high contrast photo to create a dramatic feel.