Shapefiles
Shapefile: is a simple, nontopological format for storing the geometric location and attribute information of geographic features. Geographic features in a shapefile can be represented by points, lines, or polygons (areas).[1]
References
ArcGIS. (2016). What is a Shapefile. Retrieved July 25, 2019, from http://desktop.arcgis.com/en/arcmap/10.3/manage-data/shapefiles/what-is-a-shapefile.htm
US Census Bureau. (2019, May 06). TIGER/Line Shapefiles. Retrieved July 25, 2019, from https://www.census.gov/geographies/mapping-files/time-series/geo/tiger-line-file.html