It is defined by a source of market analysis , exploration of media and a source of communication with spectator. AC Nielsen is a section of Nielsen company which was founded by Author C.Nielsen Sr in 1923 and was integrated in 1929. it has its headquarters in New York and is part of the private corporation Nielsen Group.
Explanation of ACNielsen
Basically, ACNielsen determine the behavior of media and shopping that millions of customers done throughout the world. it[s aim is to provide marketing information to its customers . This is all done through gathering of data and measurement methods , through this process they estimate that what customers watch and what they buy. it also measures ratings of public for television , radio , advertising agencies , internet companies sports , music , video games etc.