The most common solution to the low ceiling problem is installing a recessed fixture. The housing for the fixture, with all of its electrical components, disappears above the ceiling plane. The edge of the fixture is flush with the ceiling, and above, you'll see a can containing the bulb. It's minimal and simple, and provides the lighting solution that many people need. However, you must first confirm there is room above for the fixture's housing, and leave the installation to a professional.
Other fixtures, while fully visible from within a room, hug the ceiling plane and make them more appropriate for a low space. In other words, you won't smack your head on them in the middle of the night when you need a drink of water. Look for a fixture that extends less than 2 to 3 inches below the ceiling plane and incorporates translucent glass so the maximum amount of light diffuses and brightens the space.
Forget the ceiling plane at all if it is too low. Instead, focus your efforts on lighting the walls and ceiling from the walls. Install wall sconces to wash the walls with light or direct the light up to the ceiling plane. The result is a soft and even light.
For those who have no electrical skills other than plugging something into the wall, you still can light a low-ceiling room using just lamps. Lamps, predominately used for task lighting, allow you to read comfortably, can highlight a collection in the bookcase along the wall, and give off an overall welcoming and soft glow.