Dimensions are the worlds where will happen all the interesting events. Using the word "dimension" is supposed to be more strict than the "world" word because Monada itself is a world. From now and further on the "dimension" word will represent a specific thing that is inside the Monada.
Dimensions can consist of one or many Planes, mostly at areas of their intersection.
Dimensions move chaotically together with the Planes that make them up. Sometimes this moving can make two or more Dimensions to intersect and this is how walking between Dimensions can happen.