If you're thinking about selling your home, searching for a new one, or working as a real estate agent, it's important to understand your options when it comes to listings. Most homes today are listed on the Multiple Listing Service (MLS) — a central database used by real estate professionals to list properties for sale. The MLS is also the source that powers popular home search sites like Zillow, Redfin, Trulia, Realtor.com, and others. Here in the Chicagoland area, there is also a Private Listing Network (PLN), which is a subset of the MLS where listings can be shared among agents before becoming publicly available. You may have also heard about a third option — "pocket listings" or "office exclusives." These are real estate listings that are exclusive to a particular real estate brokerage's private website — that means they're not shared with the public nor any agents outside the listing brokerage.