In particular the navigation and display models inherent to HTML collapse when applied to a typical handheld device. While there are many types, styles, and classes of handheld devices, this specification is useful for a significantly larger class of devices with similar physical characteristics. This specification will use the data-ready mobile phone as an example of the typical handheld device. Physical characteristics Handheld devices are characterized primarily by a limited display size. PDA-style displays are not necessarily included in this handheld device category, although HDML will be useful on those devices as well.
Alphanumeric pagers have even fewer keys.
Item selection is accomplished through numbered lists or using cursor keys to highlight a choice and then request an action on that item. Full 2-D cursor control through pointing devices such as touch pads, touch screens, roller balls, are rare. Network bandwidth is usually low due to limitations of the network technology or simple economics. All in the name of economics. While some devices do have large amounts of memory or processing power, these devices are the exception.