Welcome to MR Ed..always best to try and 'search' first for the info you want you want to know about and then post some questions.
Do tell us (if you already know) what kind/size tank you are anticipating starting out with, and if you have any idea what kind of corals you want to keep, that info would be helpful too.
welcome to mr,its a great place to get started,just make sure you do alot of reading,thats the most important part and never hesitate to ask as many questions you need to get everything right.good luck and enjoy your stay.D