For example, the rotate plane solver is ideal for posing joint chains like the arm, where you want the shoulder, elbow and wrist joints to rotate within the same plane. See IK solvers.
See Create IK handles and Create a joint chain with an IK handle.
Note that to use spline IK, you'll need to Create spline IK handles.
You can manipulate the IK handles the same way you manipulate any other object, using the Move Tool and Rotate Tool. See also Move objects and components and Rotate objects and components.