Can someone clarify what terms mean these days?

Straight guy here and I'm hoping for someone to just clarify some terms for me. It's come to my attention that I no longer know what people mean when they say they are "trans". I don't mean to sound offensive or anything but all I can tell is that things do not mean what they meant when I was growing up. I'd just like someone to get me up to date on the most used slang of this community so I can avoid saying anything offensive in the future or misunderstanding what is being said. Thanks for any help you can provide.