The polyline command is a drawing tool found under the CAD tab, used for creating lines such as roads, trails, or ditches. Users can start by naming the poly line and assigning it to a layer, which can be newly created if it doesn't exist. Layers can be customized with color, line type, and grouped accordingly. An elevation can be set, which assigns the specified elevation to all vertices. The command allows for creating closed poly lines by choosing options like 'never' or 'if ends are close'. Points can be specified individually or by streaming. Individual points are added by clicking or typing coordinates, and commands like bearing and distance can be used for precision. Streaming points involve holding the left mouse button to draw, with vertices placed based on a set radius, useful for digitizing or tracing. For example, setting a radius of 500 feet will place a vertex every 500 feet as the line is drawn. This flexibility in input methods allows for versatile creation of 2D
polylines.