There are basicly two different cards for 3ds Games. The so called card1 games have an EEPROM chip (-> EEPROM=Yes), where the savedata is stored. Its about 1MB in size. This savedata is seperated from the ROM (for you: game) itself. Those kinds of cards are common for most games.
card2 games are a bit different. The ROM there contains a user-space, where the savegame is written. So it does not need an EEPROM to store savedata. (-> EEPROM=No) The savegames are not necessarily bigger than on card1 games but could store more data. Pokemon for example is a card2 game.