What causes water blisters what are they full of what type liquid?

What are blisters, exactly? Blisters are areas of raised skin with a watery-type liquid inside. You'll commonly see blisters on your hands or feet -- they happen because of repeated rubbing, friction and pressure. For example, if you're wearing a new pair of shoes and the shoe rubs constantly against the back of your heel, you'll likely form a blister.

Here's how it happens. A red area called a hot spot precedes your blister. As your heel rubs against the shoe -- or a strap rubs against your foot -- the skin becomes irritated and inflamed. This causes a tear to occur within the top layers of your skin, leaving a gap between the layers. Your body sends fluid to fill up this space, in order to protect it. Think of it like a small balloon under the top layer of your skin, cushioning the skin beneath.