There are numerous Driveway Types and Configuration Options
Here is a high and steep driveway in asphalt. The customer is warming it via 2 tire track paths 2' wide, the entire length. This is an economical way to make such a long and dangerous driveway passable. You don't need to heat the entire zone edge to edge to get the result.
Here is a nice gallery of a concrete condo install before and after. You can do edge to edge or any variation that makes sense. You can view the thumbnails or simply click on a thumbnail for a larger images and then view the photos in a larger size.
Asphalt radiant electric heating systems and concrete radiant electric heating systems are generally the norm. These driveway medium types are able to hold the radiant electric heat that is generated from the electric radiant cable system (nexans - high quality cable (allwarm.com) that is installed in the asphalt or concrete. The heat rises inside the medium and thus warms the driveway, melting snow and ice from the surface of the driveway. Asphalt heated driveway systems that are not electric require care and maintenance. Concrete heated driveways that are not electric require care and maintenance. Tire track paths are an option for both asphalt heated driveway installations and for concrete heated driveway installations. Tire track paths for outdoor driveway heating cut down on the square footage to be heated by the embedded radiant driveway heating system. Although to some homeowners, track paths are not as pleasing as an entire driveway zone that is cleared with in ground snowmelting, it does save money on the purchase and it still provides the customer with electric radiant driveway heating right where it is needed. Tire track widths are generally 2', two feet, paths by whatever desied length.