Article: This will show you which apps are taking up the most space. Doing so will reset that app's cached data, which will clear up some space. You may need to repeat this process for multiple apps. Some Androids allow you to clear all apps' caches at once from the Storage section of the Settings app. If this option is available, you'll see a Cached option here; tapping it will give you the option of clearing all cached data.

What is a summary?
Open the Settings app. Tap Apps. Tap . Tap Sort by size. Tap an app. Tap Clear Cache.