Erotic romance writer James Buchanan has written a
guest post at Reviews By Jesse Wave about being the T in LGBTQ. It is in large part a Trans 101, and it's notable for explicitly pointing out that trans is a spectrum, and that it includes people who are gender-fluid, and people who are dual-gendered. This matters to me -- I am quite thoroughly cisgendered, but some of my friends are not, and some of those friends do not fall neatly into the pigeonhole of "the mind is the opposite gender to the body". James also addresses the issue of transmen and women being required to conform to highly stereotypical concepts of "proper" masculine and feminine behaviour to "prove" that they're really trans and thus should be allowed to transition.[*] The post and some of the comments are well worth reading.
A word of warning: James's post was prompted by an episode a few weeks ago involving another writer, in which it became apparent that m/m romance fandom is less clueful about transgender than sf fandom is. (This is not to say that sf fandom is a utopia free of ignorance and prejudice, because it most certainly is not; it's just that as a sub-culture it's a relatively safe place to be out in comparison with the mainstream.) The comments thread at time of posting is fairly trigger-free, but there's no guarantee it will stay that way -- even with active moderation, mods have to sleep sometime.
[*I'm a ciswoman. I haven't worn a skirt in months, and I've never worn makeup outside a stage context other than at my wedding. *I* couldn't pass the test of so-called feminine behaviour that my transwoman friends and acquaintances are required to before they're allowed access to any medical support other than counselling.]