Memory card games consist of cards with your photos. The player has to find pairs of cards with the same photos. If a pair is found, it will be left open on the desk. If the player opens two cards which do not match, they will be closed again with the next mouse click. Used time and the number of attempts are counting for a score.
If you order a memory card game you specify the number of cards in the game. For each game half of this number of your uploaded photos will be selected by chance. Therefore you can upload much more photos for each game and each play will be different.
Look for example at this game with beautiful autumn photos where some cards are already opened:
While ordering you can upload your own backside for each memory card game. If you dont I take the backside with little turtles on it. Thats a nice backside anyway. But with your own backside (like the stylized autumn leaves above) you can design your game more personally.