Your listing contract should specify whether or not the house will be listed with the local MLS (multiple listing service).

It is definitely in your interest to have the house listed. This is because your sales force is automatically multiplied by however many agents are members of the local MLS and all the websites out there that publish MLS data (i.e. when you search for homes for sale on Zillow, Realtor.com, and other highly trafficked websites)

If your house is not listed, then you only have one agent working for you instead of many.