Ultraviolet radiation is a wavelength of light invisible to the human eye, but responsible for catastrophic damage to our DNA. Although our bodies have built-in mechanisms to repair DNA damage, these systems are not perfect. Essential genes in our skin cells still experience mutations as a result of UV radiation (UVR), and in some cases, this results in skin cancer. Melanoma is the deadliest form, responsible for thousands of deaths a year, and although its causes aren’t fully understood, it is clear that UV exposure is a key player in melanomagenesis. To fully understand how best to protect against melanoma, it is important to elucidate exactly how UV radiation causes the mutations that ultimately result in our melanocytes becoming cancerous. This paper will examine the current understanding of the mechanisms of UV-generated DNA damage, mutations, and tumor formation to determine what causes melanoma.