Ultraviolet (UV) light plays a significant role in DNA damage by causing the formation of covalent bonds between adjacent thymine bases in the DNA strand, leading to thymine dimers. These dimers distort the DNA helix structure, which can interfere with normal replication and transcription processes. If not repaired, such damage may result in mutations that can contribute to the development of skin cancer and other genetic disorders. Cells have mechanisms to repair UV-induced damage; however, excessive exposure can overwhelm these systems, leading to detrimental effects.