'TX' is an abbreviation of 'Texas'. 'Cis' is an abbreviation of the word 'cisgender'. Cisgender is a person who identifies with the sex that was registered for them at birth.
Yep. Like I'm a cis guy. I was assigned to male at birth, and I'm perfectly comfortable with that.
Other people are trans, or intersex, or non-binary. Biology is messy and we've got lots of variety.
Note: I might be missing something, because I'm not super familiar with all of it. I just wanted to add a little more info. I think it also helps for cisgender people to talk about this stuff too, to help normalize it. So, I chimed in.
Good breakdown, there's also gender fluid, which I believe means the gender you feel most comfortable being identified as can change. There are also neuter and newly invented pronouns, which defy the binary that many of us grew up learning about.
There's also a tremendous amount of variety within each label, even cis. Like I'm cis male also, but even between the two us we probably have different feelings about what it means to be essentially male