HTC One M8 for Windows - Manual (Page 157)

Storage
Types of storage
Want to know where you can store your apps, data, and files?
Your phone uses these storage types:
Phone
storage
Phone storage is where apps, email, data, and text messages
are stored. It can also be used to store photos, videos, and
music files.
When you are running out of phone storage, you can free up
space by uninstalling apps, changing phone storage
settings, or moving files to your computer or to an online
storage service.
Storage
card The storage card can be set as the default save location for
photos, videos, and music.
Online
storage Save your files to OneDrive and then delete them from your
phone to free up space and have access to them anywhere
you go.
Storage 157