Inside Wire and Outside Line?

What is the difference between Inside Wire and Outside Line?

Telephone lines connect to a Network Interface Device (NID) on a customer’s property. This interface is often located on the outside wall of a home or another building on the property. From this interface connection point, telephone lines extend into a house to the jack or jacks into which a telephone or equipment is plugged. The line from the NID to the jacks is called "inside wire".