Before you can play music or video on your Raspberry Pi, or even look at photos, you need to connect some content to your Pi. You can do this in three different ways: plug a USB storage device into the Raspberry Pi; connect to a storage device on your home network, or connect to a streaming media source over the Internet.
Adding a USB device
If your media files are on a USB device, plug it into a spare slot on the Raspberry Pi’s powered USB hub. A message appears in the bottom-right, confirming that the USB device is being mounted, which just means it’s being prepared so you can use it. After it’s been mounted, you can find the device in the Music, Video, and Pictures menus.
Adding networked media
If you have a media server on your home network, you can also connect your Raspberry Pi to that. For example, you might have a computer running media server software to make its music files accessible to other devices over the network, or you might have a router with a built-in media server so it can share any files on USB devices you connect to it. These networked devices most likely use the UPnP (Universal Plug and Play) standard.
You need to add the connected media device separately in each of Music, Videos, and Photos, assuming you wish to use all three content types with it. However, you only have to do this once for each content type, as Raspbmc then remembers the device’s location, even after the Raspberry Pi reboots.
To add a new connected media source for music, ...