1) Head to disk interference 
[interactivity] HDi (formerly iHD) is Microsoft`s implementation of the Advanced Content interactivity layer in HD DVD. It is used in the Xbox 360 HD DVD add-on as well as stand-alone HD DVD players. ==Advanced Content== Advanced Content is a specification defined by the DVD forum used for authoring the interactive features, such as menus, ...
Human Development Index
High Density Interconnect: High density interconnects (HDI) are defined as substrates or boards with a higher wiring density per unit area than conventional printed circuit boards (PCB). They have finer lines and spaces (<75 µm), smaller vias (<150 µm) and capture pads (<400 µm), and higher connection pad density (>20 pads/cm2) th...
Head to Disk Interference