There are three basic ways to combat backlighting:
Use a reflector or video lights to add illumination to the subject.
Lock your exposure on your subjects so they don't silhouette when the camera pans to a backlit scene.
Avoid this type of lighting all together.
Reflectors and video lights are helpful in backlit situations when you want to add light to the subject to help offset the strong background illumination.

If you're filming something that needs a steady shot, then use something like a tripod (or place the camera on a stable object), so that you get a steady shot. It's very distracting to watch something like someone speaking at a presentation, if the camera is wobbling all over the place as if it were being filmed during an earthquake.