A quick google search will provide all of this info:
CD - cross dresser - male who is usually not on hormones, but dresses and acts as female. Often, but not always, the first step in a transition. there are also many straight and gay males who cross dress.
Trans - someone who has begun the transition from one gender to another, and may be on hormones, have had surgery etc. Pre-op means they have not had gender reassignment surgery yet. Post-op means they have and present fully as their chosen gender. Plainly, a male who wants to change genders may begin as a cross-dresser, progresses to a pre-op trans and finally post-op once the process is complete.
Top - a trans provider who tops can still acheive and maintain an erection for anal sex with a client. i.e. she fucks you
Bottom - a trans provider who may or may not be able to achieve an erection, but only receives anal and does not penetrate the client
These are generalities and no explanation can ever cover the myriad of situations that occur with those in transition of their gender. Be respectful and keep the terms professional and never get into name calling. Respect the gender of the person in question, they will tell you what pronouns to use etc. With that, this thread is well and truly hijacked and will be closed. Reviews can and should be posted on their own threads.