Wikipedia prides itself on being a free-content, online encyclopedia that is editable by anyone. What this means is that you can research the basics of quantum mechanics, the migration pattern of the monarch butterfly, or details on how to blow yourself. Seriously.
Sexual content on Wikipedia can be broken down in to four categories.
In case Wikipedia's detailed descriptions of sexual acts and practices aren't enough for you to establish a mental image, Wikipedia will provide an image for you.
Anilingus - Also known as a rim-job or tossing salad. If you're still unclear, this image of a woman eating out another's asshole should help clarify it.
Anal beads - This sex toy is inserted in to and then removed from the anus for pleasure. The pleasure looks like this.
Creampie - Wikipedia describes the creampie as an "internal ejaculation" and also the "visible seeping or dripping of semen from the anus or vagina." It's also called the reverse money shot. Speaking of money shots...
Cum shot - Cum shots come in different varieties, and can result in a happy facial or a "please don't make me do this" facial. One variation is the bukkake, which can sometimes result in a refreshing beverage. Yet another variation actually results in jewelry.
Deep-throating - Women able to perform deep-throating are otherwise known as "keepers." Especially the over-the-edge technique.
Doggy style - Apparently this has little to do with canines at all, as illustrated here.
Donkey punch - Nothing says increased sexual pleasure like punching your partner in the back of the neck just prior to orgasm.
Double penetration - Many types of multiple penetration exist, but double penetration apparently is the way to go, judging by the illustrated delight on this woman's face.
Fellatio - Fellatio is pretty easy to pronounce, unless your mouth is full of cock. The 69 position is a popular variation.
Fingering - The sexual practice that begins in high school. Some women require a few more fingers than others.
Frot - Frotting is the act of non-anal, non-oral, male-to-male sex that involves direct penis-to-penis contact. Think cockrub as opposed to cockslap.
Pegging - Men, be wary of the girl who says she wants to "try something new" after purchasing a new toy, because she may just want to fill your ass with it.
Snowballing - The act of transferring a mouthful of mangravy from one person to another. This can be done from a man to a man, woman to man, or woman to woman.
Tea bag - The scrotum gargle.
Occasionally you will find that Wikipedia requires more than just illustrations to get their point across. Thankfully for us, some people are willing to showcase their genitals in front of the world.
Autofellatio - Autofellatio is kind of like an autobiography, only with less writing and more dick-sucking.
Masturbation - Whether it's ham-wallet handblasting or pork-pole stroking, Wikipedia has you covered.
Meatotomy - Some people practice genital modifications for sexual purposes. Be warned, however, that you cannot unsee a meatotomy.
Pearl necklace - As previously mentioned, a cum shot from mammary intercourse can result in this.
Apparently, even Wikipedia has limitations on what it will and will not portray. Luckily they'll still tell us about it.
Dirty Sanchez - Basically it's smearing shit on your sex partner's upper lip to emulate a mustache. Like this.
Felching - Customarily, felching has always referred to the act of sucking semen out of a recently pounded orifice. However, Wikipedia claims it also refers to Richard Gere's favorite pastime.
Rusty trombone - It's basically an anilingus and hand job combo. So yeah, pretty much exactly like playing a trombone.
Sometimes an act can be so wacky that only a video can help educate you.
Ejaculation - If the description and photo are not enough to paint a pretty picture for you, the video surely should be. And yes, it's exactly what you think it is.