The MLS is a database of all the homes listed by local real estate agents who are members of the service, which is practically all of the local agents.
Important information about your property is listed here, from general data such as square footage and number of rooms, to such details as whether you have central air conditioning or hard wood flooring. There should also be a photo, and a short verbal description of what makes your house "special."
Agents search the database for homes that fit the price range and needs of their clients. They pay special attention to homes that have been recently placed on the market, which is one reason you get a lot of attention when your house is first listed. Many agents will want to preview the home before they show it to their clients.
The main point about having your house listed in the MLS is that you expand your sales force by the number of local MLS members. Instead of having just one agent working for you, now you may have hundreds or more, depending on the size of your community.
The listing agent’s main job to make sure that the other MLS members know about your house. This is accomplished through listing your house in the Multiple Listing Service, broker previews and advertising targeted toward other agents, not homebuyers.