Internal Memory

[chun02160]

Hello!
So I have a question about internal memory.
For some reason, whenever I take a picture or put mp3 in my phone (in sd card), not only my sd card but also my internal memory goes off.
I even took out my sd memory card and look at the memory and still.

Also is there good way to manage the internal memory?
Where does cache usually located at?
I always clean up my Browser cache but is there other app causes cache?

Thanks!

[Monstrosity]

Use a file manager like astro