How 3DS data is arranged and type Core Save[/p] The core save is what is traditionally known as game's main save data is stored directly on the cart. The current save type of a 3DS game is currently restricted to EEPROM save types at the moment with the initial release of titles. The save data is currently encrypted with a basic XOR encryption. This is for the most part not directly accessible or transferable by the user. Examples of things that are stored in the Core Save: unlockable game feature, single player high scores and stats. Extra Data[/p] Using the internal save is impractile and costly to the user and game development in general. To offset such storage issues to deal with the advent of DLC (Down-Load Content), user created content and such Extra Data handles such things. Examples of things that are stored in Extra Data: DLC, game replays, user made sound files, play coins and mii characters. Extra Data is broken down into 2 types: Internal - Stored on the 3DS External - Stored on the SD Extra Data - Internal: Is not directly accessible to the user. Access to such data is done via software as the OS interface, functions of such access is limited to deleting and viewing what the content is for. Extra Data - External: Is directly accessible on the SD card. Data is located in a folder X:\Nintendo 3DS\[some numbers]\[some numbers]\extdata on the SD. (Not all games use external extra data) Game Features heavily affect the type of data used[/p] When inserting a game into the 3DS, the most basic things transfered to the 3DS are recorded into the Activity Log, both the Daily Records and Software Library record information on any cart inserted even if it is not played at all. Game icons are transfered to the 3DS and show in the Software Library. This is by definition, Internal Extra Data. Game features are listed on the back of the game box. The type of features are: Local Play Local Play is basic vs or co-op game play. This requires each person to have thier own copy of the game and uses the wireless of the 3DS to connect. The maximum number of users is based on the game. Local Play use any external extra data as of yet. Internet Internet allows for things like playing others online or DLC. Internet does create external data. There isn't any DLC available at the time of 3DS launch. Games like SAMURAI WARRIORS: Chronicles which support DLC, it is unknown as to what type of DLC is available and will likely be heavily encrypted. Streetpass Streetpass covers various features from notification to initiate vs play. Streetpass creates internal extra data used by the 3DS in Sleep mode. Streetpass is currently limited to 12 software titles at any given time. Streetpass can also access external extra data like simulated battle data. Spotpass Spotpass covers various features in which the 3DS will recieve data. Spotpass creates internal extra data used by the 3DS in sleep mode. Spotpass can edit external extra data. NOTE: This covers the basics of how most data is arranged on the 3DS.