Cement board is an underlayment material that is often used in tile flooring applications. It's main feature is that it is water proof and resistant to damage from moisture, so it can help to secure the floor against water penetration from below.
The installation of cement board or some other underlayment is relatively simple, as well as necessary, prior to the installation of hard tile. It will require both mortar and screws to fasten the sheets in place, and then fiberglass tape will have to be mortared into the joints.
With cement board it is important that you create a completely smooth, flat surface for the marble tiles to adhere to. That may require sanding down, or filling in dips or depressions that may exist in the surface of the material.
Do you have any experience working with and installing cement board? I'd love to hear more about your trials and tribulations, so please leave lots of comments below.