Legend has it that the Claddagh symbol was originated by Richard Joyce, a Galway seafarer kidnapped by pirates and sold into slavery in North Africa where he learned the art of a goldsmiths.  When he was released, nothing could keep him from his beloved Galway where he returned to become a master goldsmith and where he created the Claddagh ring.  For centuries this was used as a wedding ring by the fisher folk of Claddagh village, which nestled outside the wall of Galways city in the west of Ireland.   Claddagh rings are still worn as friends, engagement or wedding rings depending on how they are worn....

Friendship... by placing  the ring anywhere on your right hand.
Engagement... by placing the ring on the third finger of your left hand wtih the heart pointing outwards
Wedding...represented by placing the ring on the third finger of your left hand wtih the heart pointing inwards towards your heart

See how a Claddagh ring is made from start to finish - see pictures here - read more about the meaning of the claddagh Meaning of the Claddagh