It's tragic how public schools continue to fail their kids in the sexual education department. The only "sex ed" I ever got was in 8th grade and the entire week-long class was dedicated to one idea: don't have sex. Nothing about condoms, nothing about the various forms of STDs/STIs. Just good ol' "abstinence only".
So it really comes as no surprise that people between the ages of 15-24 have four times the reported gonorrhea and chlamydia rate of the population. We naively tell our children to never have sex, so then they go out and screw each other without even the slightest notion of how to go about it safely. I remember when a girl (who had been sexually active for quite some time) was shocked when I told her that she could catch an STD from giving or receiving oral sex. After I was done rocking back and forth in the fetal position and weeping for my generation, I decided to try and pick up the slack where the education system has failed.
So let's try to learn a few things, shall we?
The ONLY things that can stop you from getting an STI - other than, you know, abstinence - are condoms and dental dams. That means that if you're hooking up with a person and/or you don't know if they've been tested, you should use one of those, no exceptions. Hormonal birth control methods (such as birth control pills, the IUD, Implanon, etc.) will all protect you from pregnancy, but they don't prevent the spread of sexually transmitted diseases. This goes for sexual relations between folks with vaginas, too. Just because there isn't a penis involved does not mean there's suddenly no risk.
As I mentioned earlier, STIs can also be spread via oral sexual contact. Condoms and dental dams can be used to prevent this. Many people are often confused by the purpose of "flavored condoms" - well, there you go! And I continue to be alarmed at how many people have never even heard of dental dams, but I'm guessing that's because they're primarily associated with cunnilingus and many educators like to completely ignore the existence of the vulva.
If you're bringing any sort of dildos/vibrators/etc. into your rendezvous, it's important to know that when toys are passed between partners, they can spread infections as well. Sex toys should always be used with a condom and you should get a new condom when a different person uses the toy.
Just remember: it's better to be safe than sorry. Sexual knowledge is always a valuable resource. Do your research on safe sex and always be careful. Get tested regularly to ensure you don't unknowingly pass an STI to a partner. And, as always, the good people at Planned Parenthood have a wonderful collection of information on this as well.
Play safely, kids!