A PSTN service that is free of any toll (i.e., long distance) charges to the caller. The call actually is not toll-free, as the charges are automatically billed to the called party. In the United States, the service originally was called INWATS (INward Wide Area Telecommunications Service), although that term has long since fallen out of favor. In the United States, toll free services generally are known as 800 services, referring to the 800 area code prefix associated with such numbers. United States toll free prefixes now include 800, 866, 877, and 888. Toll free services elsewhere in the world commonly are known as Freephone or Greenphone, and the associated dial prefixes include 020, 0500, 00800, 0800, and 900.