A

ACCEL data structure: A structure that defines an accelerator key used in an accelerator table.
accelerator table: An array of ACCEL data structures, each of which defines an accelerator.
Action button: A hardware navigation control that replaces the enter key on a keyboard.
Active Channel: A Web site that has been enabled for Webcasting to information-receiving programs.
Active Desktop: A new technology delivered in Microsoft Pocket Internet Explorer that allows you to include HTML documents, ActiveX controls, and Java applets on your desktop.
active notification: The state of a user notification from the time the user is notified until the user handles the event.
Active Server Pages (ASP): An open application environment in which HTML pages, scripts, and ActiveX components are combined to create Web-based applications.
active window: In an environment capable of displaying multiple on-screen windows, the window containing the display or document that will be affected by current cursor movements, commands, and text entry. Windows CE identifies the active window by positioning it at the top of the Z order and highlighting its title bar and border.
ActiveX: All component technologies, other than OLE, that are built on the Microsoft Component Object Model (COM).
ActiveX client: An application or tool that calls an ActiveX object.
ActiveX object: An exposed object of the Component Object Model (COM).
ADC: See analog-to-digital converter.
address card: The fundamental unit of record in the Contacts database. Each address card contains information about an individual. The information consists of a set of data fields called properties.
Address Resolution Protocol (ARP): A set of programs that are part of the Internet Protocol (IP). Used to determine the hardware or physical address of a node on a local area network connected to the Internet when only the IP address or logical address is known. When an ARP request is sent to the network, the node that has the IP address responds with its hardware address.
AFD: See auxiliary function driver.
American National Standards Institute (ANSI): An organization of American industry and business groups dedicated to the development of trade and communication standards. ANSI sets standards for programming languages to use when porting programs. Internationally, ANSI is the American representative to the International Organization for Standardization.
American Standard Code for Information Exchange (ASCII): A coding scheme using 7 or 8 bits that assigns numeric values to up to 256 characters, including letters, numerals, punctuation marks, control characters, and other symbols.
analog-to-digital converter (ADC): A device that converts an analog signal, such as sound or voltage, to binary code for use by a computer.
annunciator: An icon placed onto the taskbar to indicate that a user notification is active. Although taskbars can contain multiple annunciator icons for different applications, only one instance of an icon for any given application is displayed at one time.
ANSI: See American National Standards Institute.
apartment model: A threading model that can be used only on the thread that created it. See free threading model and single threading model.
API: See application programming interface.
application-defined message: A message created by an application to be used by its own windows or to communicate with windows in other processes. If an application creates its own messages, the window procedure that receives the message must interpret it and provide the appropriate processing.
application notification: An application notification starts an application at a specified time or when a system event occurs. When an application starts as the result of a notification, the system specifies a command line parameter that identifies the event that has occurred.
application programming interface (API): A set of routines used by an application to direct the performance of procedures by a computer's operating system. For computers running a graphical user interface, an API manages an application's windows, icons, menus, and dialog boxes.
application-specific integrated circuit (ASIC): An integrated circuit designed to perform a particular function by defining the interconnection of a set of basic circuit-building blocks drawn from a library provided by the circuit manufacturer.
application switch: A hardware navigation control intended to launch or reactivate software applications.
ASCII: See American Standard Code for Information Interchange.
ASIC: See application-specific integrated circuit.
ASP: See Active Server Pages.
asynchronous operation: 1. A process in a multitasking system whose execution can proceed independently, or in the background. Other processes may be started before the asynchronous process has finished. 2. A data transmission method that allows characters to be sent at irregular intervals over a line by preceding each character with a start bit and following it with a stop bit. Compare synchronous operation.
authentication: 1. The process of verifying that a message comes from its stated source. 2. The process of verifying the identity or access level of a user, computer, program.
Automation: A technology based on the Component Object Model (COM), which enables interoperability among ActiveX components, including OLE components. Formerly referred to as OLE Automation.
auxiliary function driver: The Windows CE communication protocol manager.