American Sleep Foundation
pay attention to the position in which you wake up: most likely, you spend most of the night in this position. If you sleep on your side, choose a pillow that will support your head and neck. These are just pillows with a roller made of dense materials.
It is better for people who sleep on their backs to choose thin pillows - they reduce the strain on the neck.
Those who have a sore neck or upper back need a pillow that preserves the natural neutral position of the spine.
A recess in the middle of the pillow helps hold the head, and higher edges support the neck and relieve tension.