Chitin, a natural material found in crab shells and mushrooms, can be used to make wound dressings that speed up healing and fight infection. The review compares these two sources, finding that crab-derived chitin has been studied more extensively and has several commercial products available, while mushroom-derived chitin offers advantages like lower cost and easier processing. Both types work by promoting cell growth, stopping bleeding, and killing bacteria, making them promising alternatives to traditional wound dressings for treating difficult-to-heal wounds.