There is a necessary to have a storage device nowadays whether as entertainment or store something important.Therefore the responsibility is now be takeover by portable media centers.The functions are flexibility as storage music of mp3 or wma format.It also can be used to watch a video with a clear and great image that supported with screen resolution 320x240 pixels and bit rate less than 800 kilobytes per second (Kbps).Thus it also give a good in sound and hearing compatibility with the speaker.Any image digital also can be hold as function of this portable device and it gives a satisfy to user with clear image provided.The ability of this portable media also it can record video and sound that be recorded by the camera and it can connect to television or stereo using the A/V-out jack when portability isn't necessary.When we talk about the memory it is provided with 20 until 40gb storage capacities.In other way,it can store not less than 10,000 songs,160 hours of video, and thousands of digital photograph.


source : http://electronics.howstuffworks.com/pmc.htm