The launcher as well as CAS/Build/Buy Menu have little icons next to clothing/objects/etc. Those icons give you an indication where the item came from.
The launcher has two different icons
This lets you easily distinguish if something is a third party content or came from the Sims3 Store. Houses, worlds and Sims that you download from the Exchange or other sites are displayed as CC.
CAS/Build- & Buy Mode
CAS/Build and Buy Mode have some extra icons but the red flower that indicates cc does not display. All downloads that are installed through the launcher show as if they were bought in the Store.
Clothing and objects without an icon are from the base game.
Objects and clothing that have show the EP icon came with that EP.
Folder icons can be package files, files that came directly with a Sim or something you saved ingame. There’s no way to distinguish between the three.
You should know what you created yourself though.
The Store Icon was supposed to be for Store items and all other Sims3Packs should have the red flower like presented in the launcher. For whatever reason all Sims3Packs are displayed with the Store Icon ingame.