The field of "AAL Robotics", combining AAL and robotics as disciplines, has not yet been precisely defined and does not present accepted structures and concepts that would allow to communicate unequivocally its methods, projects, and approaches. The paper presents a method of defining and categorizing AAL robots and presents the resulting classes of robots with regard to the activities they assist. The classification is useful in that it is able to cover the breadth of the field, but a more fine-grained description of functionalities will be needed in further research to establish the potential of robots to assist independent living of older adults.