Offering maṇḍala (or mendel) is part of the practice of offering. In this practice, one makes the offering of the entire universe or world, as one perceives it. The fundamental concept underpinning the maṇḍala offering is giving all good things which exists in the entire universe to one’s guru, the Buddha or the Bodhisattvas.
Maṇḍala offering is a very extensive but comprehensive method of offering because when one offers the whole universe or the world, everything is included in it. We include both the external world - the container or noe – with all the contents or chue. Thus, maṇḍala offering is all inclusive.