ye macbook ki back side ha ye air system k liye estamal hota ha. e ski waja se system garm ni ho pata ye system ko thanda rakhne ka kam ata ha. e ski waja se system ki memory set rehti ha. yes system ki performance behter bane k ba kam ata ha. e ski waja se kai dafaa system me pankha lagana ki b zarorat nai parti ha ye ak bht mufeed system ha.