why is my Android phone full when my stuff isn't taking up much space?

[Android Central Question]

My Samsung phone is showing I am using up 15.4GB of space but whn i look in storage my apps and photos & docs only come up to 3GB. what is the rest of it??

 

[belodion]

Cached data?

 

[B. Diddy]

Welcome to Android Central! Which phone? Show us a screenshot of the Settings>Storage menu: http://forums.androidcentral.com/ge...ide-how-post-screenshots-android-central.html. You'll have to register on this forum first. https://forums.androidcentral.com/ask-question/409154-join-android-central-community.html

The DiskUsage app can also be helpful.