Now, we will move on to creating line features. These are more complicated because they require multiple vertices. At a minimum, a line requires two vertices: a beginning and an ending. It is not uncommon for a line feature to have multiple vertices. This is called a polyline.

As far as ArcGIS is concerned, a line and a polyline are the same thing. They are stored together in the same feature classes and the tools that are used to create them are the same. So, you will see the terms line and polyline used interchangeably within ArcGIS. This is not true of all applications, such as AutoCAD.

Line features stored in a geodatabase feature class can also include curved segments. These segments are stored and created as arcs. Not all data storage formats support arcs. A shapefile is a good example of one that does not support arcs. Instead of using arcs, a shapefile typically uses multiple very short straight segments to simulate the arc. When displayed to...