The Derived Data Cache (DDC) stores versions of Assets in the formats used by the Unreal Engine on its target platforms, as opposed to the source formats artists create that are imported into the Editor and stored in
.uasset files. Content stored in the DDC is disposable in that it can always be regenerated at any time using the data stored in the
.uasset file. Storing these derived formats externally makes it possible to easily add or change the formats used by the engine without needing to modify the source asset file.