HD-DVD
     Also uses blue-violet laser.

     Alternative protocol/design.

     DVD-R:  15GB single layer / 30GB dual layer.

     DVD-RW:  20GB single layer / 32GB dual layer.

     Endorsed by the DVD forum.
  
     To market in March 2006.

     Not protocol compatible with Blu-Ray 

     Backwards compatible with DVD
       HD-DVD disks (custom) can contain standard DVD data, readable by DVD
       HD-DVD format can encoded on a standard DVD (short format)  
       HD-DVD players can read standard DVDs with no problems.
  
     Approx 30% less storage than BluRay 
       but technology more affordable.
   
     Used a Microsoft based menu system.