Up Volume, Home Screen Button, Power Button

[mrtwohands]

I went to clear my phones cache today and saw these other options but I am unclear what they do. Can someone explain what they are for what is the benefit of them, if any.
Apply update from ADB
Apply update from external storage
Apply update from cache

 

[B. Diddy]

Those options are used if you want to manually update the OS with a ROM that you downloaded. Unless you're interested in rooting and loading custom ROMs, just ignore them.