STI stands for Sexually Transmitted Infection. These are infections that people can get when they have sexual contact with someone who already has an infection. It’s kind of like how you can catch a cold from someone, but instead, these are passed through sexual activity — like vaginal, oral, or anal sex. Sometimes, people don’t even know they have an STI because the symptoms don’t always show up right away.Common Types of STIs:Chlamydia - This is one of the most common STIs. It’s caused by bacteria and can infect both boys and girls. If not treated, it can cause problems later like not being able to have kids. It can be silent, meaning you might not feel anything, but it’s still there.Gonorrhea - This one is also caused by bacteria. It can cause pain when peeing and unusual discharge from private parts. Like Chlamydia, it can also affect the ability to have children if ignored.Syphilis - This STI happens in stages. First, there might be a small sore, then rashes or flu-like symptoms. If left untreated for years, it can cause serious damage to the body — even to the brain and heart.HIV (Human Immunodeficiency Virus) - HIV is a virus that attacks the immune system. Over time, it can lead to AIDS, which makes it really hard for your body to fight off other diseases. It spreads through blood, semen, and vaginal fluids — not just sex, but also sharing needles or injections. Genital Herpes (HSV) - This is a virus that causes painful sores or blisters around the private parts. It stays in your body for life, and while there’s no cure, medicine can help manage it.HPV (Human Papillomavirus) - This virus can cause warts on the private parts and, in some cases, even cancer (like cervical cancer in women). There is a vaccine to help protect people from HPV.