Did you know that about half of sexually active teens and young adults will get an STD before their 25th birthday – and many of them will have no idea? If you’re having any kind of sex, you need to think about sexually transmitted diseases (STDs). Since the most common symptom of STDs is having no symptoms at all, the only way to know for sure is to get tested. Remember, knowledge is power and safe is sexy. And don’t worry, testing is confidential and might even be free.