In families, people call each otherr from the viewpoint of the youngest of the family. A parent calls his/her eldest son or daughter おにいちゃん(elder brother) or おねえちゃん(elder sister) respectively, standing in the position of his/her younger sister or brother.
When parents talk in the presence of their children, the husband calls his wife おかあさん or ママ(mother), and the wife callls her husband おとうさん or パパ(father). This pratice, however, has been changing recently, and the number of couples who call each other by their name is increasing.
In society, people call each other by the names of their role in the group to which they belong.
At work, a subordinate calls his boss by his job tilte (部長、課長、社長、etc.).
At shops, a shop assistant calls his/her customer おきゃくさま or おきゃくさん.
Doctors are called せんせい by their patients.