Chasers used paper maps for navigation and some of those now using GPS still use these as a backup or for strategizing with other chasers. Foldable state maps can be used but are cumbersome due to the multitude of states needed and only show major roads. National atlases allow more detail and all states are contained in a single book, with AAA favored and Rand McNally followed by Michelin also used. The preferred atlases due to great detail in rural areas are the ""Roads of..."" series originally by Shearer Publishing, which first included Texas but expanded to other states such as Oklahoma and Colorado. Covering every state of the union are the DeLorme "Atlas and Gazetteer" series. DeLorme also produced early GPS receivers that connected to laptops and for years was one of two major mapping software creators. "DeLorme Street Atlas USA" or "Microsoft Streets & Trips" were used by most chasers until their discontinuations in 2013. Chasers now use Google Maps or other web mapping as no suitable alternative mapping software emerged. GPS receivers may still be used with other software, such as for displaying radar data.