My friend recently told me that they think they’re non-binary, and don’t really feel like either gender. I just don’t get it—there are only two genders, right? I don’t always feel 100% like a girl (I don’t like wearing skirts and I like watching sports), but that doesn’t mean I’m not one, does it?

This is such a great question! Gender is a surprisingly complicated topic with a lot going on. It can also be a very personal subject. You should feel proud that your friend trusts you enough to talk about it!

To begin with, though: You’re not transgender just because you don’t like typically “girly” things.

Everyone, regardless of their gender, acts in all sorts of ways. In fact, what’s considered “girly” changes depending on where in the world you are, and what time period you’re in. Did you know that the color pink used to be considered “manly” in the United States? Or that high-heels were originally worn by men? These expectations about what boys and girls should like and do are called gender norms, and there’s no medical basis for them. They’re cultural. In fact, gender itself is cultural, and not medical. You’re not any less of a girl because you don’t fit into the specific gender norms of the USA in the year 2017.

As for the other part of your question: No, there are not only two genders.

However, many people still talk about gender like you can only be a man or a woman, so it’s perfectly understandable that you’re thinking about it this way. This idea that there are only two genders is called the gender binary. Your friend, by identifying as non-binary, is rejecting that idea.

To understand why there are more than two genders, it’s useful to think of a color gradient, with black slowly turning into white. A gradient has limitless variations of color, not two options between “white” and “black.” Think of gender this way, with “man” being one end of the spectrum, and “woman” being the other. This is called the gender spectrum. Some people are even outside this spectrum altogether! When your friend says that they’re non-binary, they mean that they fall somewhere along that gradient. However, only your friend can explain exactly where they fall, or whether it changes day to day.

While some cultures reject the idea of the gender spectrum, others have recognized genders beside “man” and “woman” for thousands of years. Keep in mind that while individual and cultural understandings of gender vary, mental health guidelines (such as from the American Psychological Association) encourage mental health professionals to think of gender as a spectrum.

It sounds like your friend isn’t out as non-binary yet.

If and when they do come out, you can support your friend by explaining the gender spectrum to people who may not understand it. Explaining that being non-binary is just as normal as being a girl or a boy could really help others accept your friend for who they are.

Gender is a super complicated subject with a lot of terminology, and there’s a ton more to learn! Educating yourself is one of the biggest ways that you can show your friend you support them. Try checking out the Gender Unicorn for a visual explanation of gender identity, expression, and attraction. This article answers some common questions about being non-binary, and this article goes into more detail about what gender is and different ways people experience and express it. Gender Spectrum is a great resource to continue educating yourself, too.