Bisexuality is the attraction to two or more genders. It can be used as an umbrella term that refers to any sexual identity that has attraction to more than one gender, but is also a sexuality itself that means attraction to two or more genders. Some identities under the umbrella are also pansexual, omnisexual, bi-curious, and polysexual.
Please note that bisexuality includes trans people, all of them, meaning non-binary people, too. Not all bisexual people are attracted to male and female, all genders, or non-binary people. It is a broad term used to describe anyone with attraction to more than one gender. AGAIN, note that sex is restrictively male, female, and intersex, while gender is a broader spectrum.
Stella: I identify as bisexual.
Audrey: So like.. girls and guys?
Stella: Not exactly, some bisexual people only like those, but I like almost any gender, I don't really care personally. No matter what all of use are valid though.
Audrey: Doesn't that make you pansexual? Or Queer?
Stella: While some bi people can be pansexual, they might just identify as bi because it makes them feel comfortable, that's how it is for me. Besides, that label doesn't even match my attraction! Same with queer, it just isn't me.