Protective layers are barriers that shield objects or living beings from damage or harm. These layers can be physical, like the skin of a human or the bark of a tree, which help prevent injury from external elements. They can also be chemical, such as coatings on metal to prevent rusting, or even biological, like the immune system in animals that defends against infections. In various contexts, protective layers serve specific functions. For example, in packaging, protective layers keep products safe during transport. In construction, insulation materials act as protective layers against temperature changes. Overall, these layers play a crucial role in maintaining integrity and safety.