Files with the extension SHP contain data in ESRI shapefile format. It is the main file of this standard, which contains the actual geometry data.
For use but usually more files are necessary. Especially the index with the ending shx and the dbf database. There are still optional files eg Atx, sbx, sbn, aih, ain, prj and cpg, which contain further special information, but do not always have to be present.
The ESRI shapefile (shapefile) is a popular spatial vector format for Geographic Information Systems (GIS) developed by ESRI's largely open specification for ArcGIS, which is used to exchange data between various products of ESRI and other manufacturers.
These files are not only used by actual GIS applications, but also by other systems that work with GIS data or forms, eg the CARE-S channel maintenance system.