IDF also stands for intermediate distribution frame .
An interface device (IDF) is a hardware component or system of components that allows a human being to interact with a computer, a telephone system, or other electronic information system. The term is often encountered in the mobile communication industry where designers are challenged to build the proper combination of portability, capability, and ease of use into the interface device. The overall set of characteristics provided by an interface device is often referred to as the user interface (and, for computers - at least, in more academic discussions - the human-computer interface or HCI ). Today's desktop and notebook computers have what has come to be called a graphical user interface ( GUI ) to distinguish it from earlier, more limited interfaces such as the command line interface ( CLI ).
An interface device generally must include some form or forms of output interface, such as a display screen or audio signals, and some form or forms of input interface, such as buttons to push, a keyboard, a voice receiver, or a handwriting tablet. Harmonia, a company that makes a program for developing Web pages that can be formatted on the fly for different kinds of interface devices, defines six generic classes of interface devices that characterize today's technology:
- The personal computer (desktop or notebook, abundant memory and external storage, keyboard, large display)
- Handheld (much smaller, still has a keyboard)
- Palm (smaller still, can fit in some pockets, handwriting is primary input interface, display very small and usually landscape rather than portrait)
- Smart Phone (digital cellular phone with little or no computing, accepts Wireless Markup Language-coded pages from Web servers)
- Smart Pager (also known as a two-way pager , has the ability to respond by pressing buttons or by using a tiny keyboard)
- Standard Telephone (voice and key input interface, no computer capability)
- Hybrid (often a combined phone and handheld computer)
If you are creating content for a human receiver, you need at least a general understanding of the type or types of interface devices that the your audience may be using. The Extensible Markup Language ( XML ) is designed to allow Web or other content to be created independently of the type of interface device that may be used. An individual style sheet designed for specific interface device types can be created using the Extensible Stylesheet Language ( XSL ). Then, when a user requests a page, that user's interface device type can be recognized and the appropriate style sheet used to format the page that is sent. Harmonia has developed a User Interface Markup Language (UIML) that facilitates this process.