Of all the great things in life, sex can be one of the most rewarding.

When done correctly, regular sex can improve your relationship and sense of wellbeing . Not to mention it feels pretty darn good. But if you're a man who has sex with women, there's one thing you'll need to master before you can achieve the highest levels of sexual pleasure. It's the...

When it comes to the female reproductive system, things can get complicated fast. Yes, the vagina -- a term often used when people really mean the vulva -- can be delicate and complex (and also, by the way, tough AF ).

A man's understanding of the vagina can dramatically affect his love life. Basically, if you're well-versed in vag, chances are your partner will want to get randy more often, thus leading to a slew of health benefits for the both of you.

Studies show that men who have sex at least twice a week have better heart health and lower risk of cardiovascular disease. Good sex also releases endorphins, which can reduce stress and improve sleep for everyone.

But better sex and foreplay don't magically happen overnight. That's why we put together a list of 7 things men should know about the vagina, so they can master the fine art of good sex.

1. When you say "vagina," you probably mean "vulva."

Technically speaking, vagina refers to the muscular, elastic canal which leads to the cervix and uterus. This is the "hole" where the penis or fingers are (usually) inserted and through which babies pass during birth.

"Vulva" is the term that describes all of the external organs that make up female genitalia . Basically, it's everything you're looking at when you're down there. The vulva includes the vagina, the pubic mound, the labia majora (the outer folds of the vulva) and labia minora (the smaller, inner folds), the opening of the urethra (the pee hole) and the clitoris (more on this very important part later).