When hair is dry, the cuticle has become heavily weathered and porous and cannot retain water. Friction, heated appliances, chemicals and overexposure to the elements are the most common causes, but any combination of drying factors can take moisture out of your hair.
When hair looks and feels dry, it tangles easily and is difficult to comb. Dry hair tends to be more of a problem in long hair, simply because the hair has had a longer life to endure more wear and tear.
The good news is that most healthy hair can withstand the occasional appliance mishap or weather run-in. It's repeated damage from things like chemical over-processing and frequent styling that can leave your hair thirsting for moisture.
