A frame comprises a frame name, slots or attributes of the frame and facets. For clarification, frames can be classified into class frames and instance frames. Class frames are used to describe group of objects or class of objects and can also be organized into taxonomy. A class frame therefore has parent and children as common slots. Slots from a parent frame can be inherited to its children. Instance frames, on the other hand, describe particular object instances. They are the leaf node of the taxonomy and have no children.