You must have an HD television, and also an HD cable or satellite box, and also the TV show or program must have been filmed in HD. For movies on a disc, you'll need a Blu-Ray player. Everything must be plugged into the TV with HD cables such as an HDMI cable. Another lesser-known option, is using an antenna to pull in local channels in HD. For this, plug in an antenna or rabbit ears into your HD television, and tune to a local channel broadcasting in high definition. This does work as I use an antenna in my own home.