# Object (Connector) A Connector is a special Object, which links two or more markers. A Connector which is not a Constraint, is a force element (e.g., spring-damper) or a penalty based joint. ```{toctree} :maxdepth: 1 objectConnectorGeneral ObjectConnectorSpringDamper ObjectConnectorCartesianSpringDamper ObjectConnectorRigidBodySpringDamper ObjectConnectorLinearSpringDamper ObjectConnectorTorsionalSpringDamper ObjectConnectorCoordinateSpringDamper ObjectConnectorCoordinateSpringDamperExt ObjectConnectorGravity ObjectConnectorHydraulicActuatorSimple ObjectConnectorReevingSystemSprings ObjectConnectorRollingDiscPenalty ObjectContactConvexRoll ObjectContactCoordinate ObjectContactCircleCable2D ObjectContactFrictionCircleCable2D ObjectContactSphereSphere ObjectContactSphereTorus ObjectContactSphereTriangle ObjectContactCurveCircles ```