While HD Radio is the hottest technology today, HD DVDs are another new technology that will soon allow you to view high definition movies on DVD right in your living room.

What are HD DVDs? It depends on whom you ask, as there are currently two competing HD DVD formats under development. Both support high def films but one goes by the easy to remember name, HD DVD. The other is called Blu-ray.

An HD DVD disk has a single layer capacity of 15GB and a dual-layer capacity of 30 GB. And Toshiba is developing a triple layer disk that will have a capacity of 45GB. However, this is still smaller than Blu-ray disks, which support 25GB for one layer, 50GB for two layers and 100GB for four layers.

This means that both formats will be able to play movies and programs recorded in high definition but, as you would imagine, the larger capacity disks will be able to support more additional information such as out-takes, director