The multiple listing service, or MLS, is a facility that allows real estate professionals to learn about and share local property listings in support of the interests of clients and customers. REALTORS® enjoy an economical, efficient system of sharing real property information and facilitating cooperative transactions, while their clients and customers have access to the most accurate and up-to- date property information available. There are hundreds of MLSs across the country, which use a common set of rules to enable a smooth exchange of information in their local communities. MLSs provide a means for participants to offer compensation to other participants and enhance cooperation among them. As applications of Internet technology to the real estate business have increased in number, quality, and acceptance by the public, most real estate brokerage firms have established "online identities." MLSs have adopted Internet Data Exchange (IDX) programs as a means of enhancing cooperation between REALTORS®. Under IDX, brokers exchange consent to display each other’s listings on participants’ websites and using applications for mobile devices that participants control. Many MLSs, as a service to their members, also provide listing information to third-party aggregators such as realtor®.com and others through syndication or other similar type agreements, unless the broker withholds consent.