While often used interchangeably, SPF (Sun Protection Factor) is the measure of how well a sunscreen protects skin from UVB rays. Sunscreen is the product itself that provides this protection, with the SPF number indicating the level.

Sunscreen is the actual product, while SPF is a rating of its protective ability. You need sunscreen to get SPF protection, so focus on choosing a sunscreen with an adequate SPF level (SPF 30 or higher is generally recommended).

SPF 50+ is often used when a product has a very high SPF, typically exceeding SPF 50. While it might offer slightly more protection, the difference between a well-applied SPF 50 and SPF 50+ is minimal, and consistent application is key.

SPF 50 blocks about 98% of UVB rays, while SPF 30 blocks about 97%. While SPF 50 offers slightly better protection, the difference is small, and proper application (generous amount, reapplied every two hours) is more crucial than the specific SPF number.