Diagram rails are entities used to represent power or ground circuits. Rails are created in a manner similar to highways.

Rails can be attached to components, connectors, other rails, or can be left unattached. Multiple wires can be attached to rails.

Unlike highways, rails can contain parameters. The only required parameter is NAME. All other parameters are user-defined and can be modified using the same method as the one used to modify wire parameters. Like highways, rails can be broken into several views.