STDs are sexually transmitted diseases spread through sexual contact and bodily fluids. Anyone who is sexually active can contract an STD, which may cause symptoms like sores or rashes or no symptoms at all. Common STDs include chlamydia, gonorrhea, herpes, genital warts, and HIV/AIDS. STDs can be prevented through abstinence or using condoms during any sexual contact to avoid transmission. It is important to take STDs seriously as some can permanently impact one's health if left untreated.