Each line is determined by a starting pair of coordinates and an ending pair of coordinates. These lines can have ends, or nodes, which are either connected or disconnected. Nodes which are connected together to enclose an area form polygons. Pictures are made up of these segments. These vertices can be as close together or far apart as the file allows.
Disconnected nodes form line segments or arcs.
The other data type that is in vector data is point data. Instead of a point connecting to a line segment, these points might denote specific locations, like the top of a mountain.