Although STDs (other than AIDS) generally won't kill you, some of them, if left untreated and undetected, can leave you infertile, which is bad enough. Here's a rundown of the most common STDs.
Bear in mind that some STDs share symptoms (like itchy genitals, burning, difficult urination and foul-smelling discharge) with other "crotch concerns," including urinary tract infections, yeast infections, bacterial vaginosis and trichomoniasis--infections that can also result from sex.