The risk of HIV infection is magnified for men who have sex with men (MSM), especially minority MSM < 30 years of age and with substance use problems. A promising approach to HIV prevention among this high-risk population is the targeted promotion of HIV self-testing, simplified access to test kits and seamless linkage to pre-exposure prophylaxis (PrEP) medication. This project seeks to compare the relative effectiveness of using social media sites versus informational sites like to promote HIV self-testing and PrEP uptake. MSM between 18-30 years old will receive culturally-relevant advertisements targeting minorities similar to those previously developed. Specifically, the study aims to 1) adapt existing social media-based HIV self-testing and PrEP advertising materials for digital distribution on social media and informational sites and 2) compare the effectiveness of HIV testing and PrEP uptake promotion across social media sites versus online informational platforms.