The concept of Trinity or the triple diety is shared by many mythologies and current religions. They represent virtuous traits and/or important beliefs of their culture.

Bramha-Vishnu-Siva (Mahesh) 

The Hindu Trinity

Zeus-Posiedon-Hades

The rulers of Olympus, The Seven Seas and The Underworld (Hades) respectively 

Osiris-Isis-Horus

One of the many Egyptiant Trinities

Odin-Vili-Ve

The First of the Æsir