A shapefile is a vector file format used in GIS mapping to represent real world objects by storing information about their location, shape, and attributes of geographic features on a map. There are three basic types of shapefiles: a point, a line, and a polygon. A point file is a single x,y coordinate that represents a geographic feature. Depending on the scale of the map points can represent a variety of objects including cities, wind turbines, or garbage cans. Lines represent features that have length and direction but no area that connect at least two x,y coordinates. Common examples include roads, water lines, and rivers. A polygon is a two-dimensional closed figure with at least three sides that represent an area. Polygons are used to show buildings, agricultural fields, or other boundaries.