Everyone has a gender identity. They may be men, women, non-binary, or another gender. A trans (transgender) person before transition may know they’re one gender, but others may assume they’re another. A “Cis” (Cisgender) person knows that their gender is the same as the one they were born with. Some transgender people identify as neither male nor female, or they may identify as both. There are a variety of terms that people who aren't entirely male or entirely female use to describe their gender identity, like non-binary, non-conforming, queer, and genderqueer.
For a trans person, “transitioning” means beginning to live as their gender identity, including changing things like their name or the clothes they wear. For others, transition may mean taking hormones or having surgery. Trans men may be attracted to men and identify as gay; be attracted to women and identify as straight; or be attracted to both and identify as bi.
In the US, the National Center for Transgender Equality has resources for both trans people and people who want to know more about trans issues. Here is a list of resources in some other countries. The Trans Lifeline also has resources for trans people in trouble.
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