Nichtlustig Doppelgänger

First published in today's form by Ravensburger in February 1959.

There are versions knows from Japan in the 16th century - matching pictures painted on shells. Known as Awase or Kai-awase.

In USA and England known as Pairs, Pelmanism, or Concentration. But these are played with simple playing cards.

In Switzerland was a domino-like game named Zwillingsspiel with the same roots.

There are hundreds of different Memory games - starting with 24 cards for the youngest, with all kinds of animals, art, about countries, also a gay and a "Breast Memory", several free giveaway Memory games published by companies.

The most famous publisher is Ravensburger - they have the rights for the brand name Memory - and they have really nice ones.