UV and SPF are two frequently heard abbreviations when talking about sunburn prevention.

UV stands for ultraviolet and is divided into the UVA, UVB and UVC sub-bands. The Earth's atmosphere filters out a portion of these before they reach the planet's surface. UVC is almost entirely eliminated by the atmosphere, but UVA and UVB penetrate in significant amount that sunburn can occur in less than 15 minutes.

SPF stands for Sun Protection Factor and is used to measure the effectiveness of sunscreen. The higher the SPF number, the better the protection against the sun's ray. SPF numbers indicate the length of time you can stay under the sun without getting burned. For example, if it takes 15 minutes for a person to get sunburn, an SPF 15 sunscreen will allow them to stay out in the sun 15 times longer without burning. A minimum SPF 15 rating is recommended for general UVA and UVB ray protection.