Component roads are configurable component roadway assemblies that also use vertical and horizontal geometry to offer more precise control of geometry and grades. You can add component roads in-canvas, or convert planning roads to component roads. Component roads support advanced modeling and analysis features such as corridor and profile optimization, sight distance analysis, superelevation, linear road transitions, as well as traffic and mobility simulation. See About Component Roads.
Planning roads are lightweight roads that use spline geometry. These are the default roads drawn by Model Builder. You can add planning roads to a model or import roadway data as planning roads. See: To add or modify roads.