Use Protection

Probably.

By certain activities do you mean sex? Anyone can get AIDS and HIV if you are having sex, gay straight or in between AIDS and HIV affects us all and the more people who take charge and wear the right protection the better chance we have of stopping it.

They protect you against HIV, which can then turn into AIDS if it's not treated quick enough. HIV has no symptoms so millions of people have it and they wouldn't even know until it turns into AIDS, which is why it's important to use a condom.

HIV (the virus that "gives" you AIDS) is only sexually transmitable and transmitable through birth (mother to child). What did you think?

HIV: Human immunodeficiency virus. When this thing takes over, it kills your immune system, and then just waits. Like an army destroying the enemy's defences and then just staring at them.
AIDS: Acquired immunodeficiency syndrome. This isn't actually the HIV, it's any (or a mix of) virus or cold that comes in, but since your immune system is dead (Note: You have to have had HIV before AIDS) even the common cold can kill you. Like another tiny army coming into the fortress and murdering everyone inside without working against the barriers.
Remember, unprotected intercourse/inherency -> HIV (Not always, but) -> AIDS -> Death (Unless you're lucky)
-StrangelyAcoustic (Holy crap, how did I get here before FunStats!)

Condoms protect you against HIV and other STDS, they aren't perfect with a rate of 76-99% but its better than nothing. The best thing is to get regularly tested, use multiple forms of protection and talk with your sexual partners before sex about their sexual history.