Cervical contour pillows are the best option for most people.
With a cervical contour pillow, your head will rest in a depression in the middle of the pillow.
Your neck will rest on either side.
If you lay on your back, your neck will lay on a less elevated side, and if you lay on your side, you will lay on a higher side.
Next to cervical contour pillows, foam contour pillows are the next best at supporting your neck.