A portable media player or PMP is a device that can play and record various types of media, most notably video. Media players tend to be larger than MP3 players due to the fact they have larger storage capacities and larger LCD screens to display photographs and video.
In general a portable media player is able to play music files, video files and allow you to view photographs. Video and images can be viewed on the built in LCD screen and usually there is the ability to view your video and images on your TV via a video cable that is usually included in the package when you buy.
As well as being able to play video many players are able to record video straight from your DVD player or from your TV. If a media player does not have this ability you can still copy video files from your computer to the player.
Some players will also include a TV tuner or a radio tuner. These will allow you to watch TV or listen to radio on a portable media player.
If you are into digital photography then a portable media player with a built in Compact flash or Secure digital reader means you can transfer your digital pictures onto the player without the need for a PC.