There are many types of STIs. When Syphilis was first able to be treated with Penicillin, new treatment for STIs have become available. Gonorrhea and Chlamydia are the most common STIs, but there are more! Learn about the different types of STIs and how to prevent them. Learn what is and what is NOT a STI. Learn about treatment and new vaccines available! Better yet, learn how to prevent getting or spreading the disease!