If it is that basic information you are searching for, then I would strongly suggest that you go to the nearest book store and get some of the following:
You DO have to read about the subject to determine what it is all about, what you want, want you can realistically afford, etc... There is one heck of a learning curve involved with marine aquariums and marine fish keeping, and it is far from being cheap too.
Do a lot of reading and internet search before jumping in, to save yourself some time, money and grief.
Good luck and welcome to the site.