This is a very interesting question. Let me break it down for you and help you understand all the things you need to consider in order to choose the right pillow for you.
1.Consider your preferred sleeping position.
If you want to sleep on your stomach, you may need a soft, flat pillow so that you don’t overextend your neck and feel uncomfortable.
If you are someone who prefers to sleep on your back most of the time, you should use a pillow of medium thickness. A very firm person or a very soft person will push the head forward or sink it and limit its alignment with the spine, respectively.
If you are a sleeper, choose a thick, firm pillow for optimal neck support in that position.
2.Consider the pillow’s filling material.
If you are allergic to certain materials, consider what they are and make sure that the filling does not cause medical complications.
Fillings such as feathers on pillows tend to stiffen the pillow, making it ideal for side sleepers, but may cause allergies.
Cotton and wool-filled pillows are safer in terms of allergies, but they tend to be firm, making them uncomfortable for stomach sleepers.
The latest addition is a memory foam pillow that provides strong support for the neck and spine. Perfect for people who mix and match sleepers, i.e., those who sleep in multiple positions.
3.Consider special pillows.
The anti-pillow claims to help position the head so that the airway remains open by lifting the chin away from the chest.
Cool pillows are designed to include padding that absorbs head heat to keep you cool. While they can be used by anyone who wants to stay cool at night, they may be especially suitable for people who suffer from hot flashes.
Oxygen pillows are designed to promote air circulation, with the goal of helping you breathe more freely and deeply while you sleep.  Despite claims that this helps relieve pain, doctors aren’t sure how or if this technique actually works.
An orthopedic pillow is a pillow designed specifically to correct the position of the body in bed or on any other surface on which you lie. It is designed to meet orthopedic guidelines to ensure proper placement and support of one or more specific parts of the body to provide a safe and healthy rest for lying down. You can find the Recron-approved product, called Dr. Ortho, here.
Finally, consider all of the basics that a conscious customer will want to consider when purchasing any product, such as reviews, warranty, support and even cost differences. I recommend a Recron certified brand that is usually my first choice for sleep products.