Operating systems terminologies:

ActiveX: A Microsoft technology that enables different programs to share information. ActiveX extends Microsoft Windows-based architecture to include Internet and corporate intranet features and capabilities. Developers use it to build user interactivity into programs and World Wide Web pages.

Adaptive Delta Pulse Code Modulation (ADPCM): A method of compressing audio data. Although the theory for compression using ADPCM is standard, there are many different algorithms employed. For example, Microsoft's ADPCM algorithm is not compatible with the International Multimedia Association's (IMA) approved ADPCM.

Algorithm — A sequence of instructions describing how to perform a specific task. Algorithms are often implemented in a computer language and compiled into a computer program. In the context of effects units, algorithms usually describe a software building block designed to create a specific effect or combination of effects.

Application (App) — Alternative term for computer program.

Audio Compression Manager (ACM): The Audio Compression Manager, from Microsoft, is a standard interface for audio compression and signal processing for Windows. The ACM can be used by Windows programs to compress and decompress .wav files.

Beta Version — Software which is not fully tested and may include bugs.

Binary — A counting system based on only two states: 1s and 0s. It is ideal for electronic equipment where it can be represented as high and low voltages, light on/off, N-S or S-N magnetic domains, etc.

BIOS — Part of a computer operating system (basic input-output system) held on ROM rather than on disk. This handles basic routines such as accessing the disk drive.

Bit — A contraction of Binary digit, which may either be 1 or 0.

Buffer Memory — A buffer is essentially a short term data storage facility used to accommodate variable data read or write periods, temporarily storing data in sequence until it can be processed or transferred by or to some other part of the system.

Bug — Slang term for a software fault or equipment design problem.

Byte — A collection of digital data comprising eight bits.

Codec: Coder/Decoder: refers to any technology for compressing and decompressing data. The term codec can refer to software, hardware, or a combination of both technologies.

Compression Ratio (file size): The ratio of the size of the original uncompressed file to the compressed contents. For example, a 3:1 compression ratio means that the compressed file is one-third the size of the original.

Computer — A device which can be instructed (or programmed) to carry out arithmetic or logical operations. Although mechanical 'analogue' computers do exist, most are now electronic and digital, and process digital data.

Copy Protection — A method used by software manufacturers to prevent unauthorised copying.

CPU — Central Processing Unit — the number-crunching heart of a computer or other data processor.

Crash — Slang term relating to malfunction of computer program.

Data — Information stored and used by a computer.

Defragment — The process of rearranging the files on a hard disk so that all the files are as contiguous as possible, and that the remaining free space is also contiguous.

Device Driver: A program that enables Windows to connect different hardware and software. For example, a sound card device driver is used by Windows software to control sound card recording and playback.

Digital Rights Management (DRM): A system for delivering songs, videos, and other media over the Internet in a file format that protects copyrighted material. Current proposals include some form of certificates that validate copyright ownership and restrict unauthorized redistribution.

DirectX: A set of Application Program Interfaces designed by Microsoft for multimedia development. A DirectX plug-in, such as the Noise Reduction DirectX Plug-In, uses the DirectX Media Streaming Services (DMSS) API. Because DMSS is a standard API, a DirectX plug-in can be used in any application that supports DMSS.

DMA — Direct Memory Access. Part of a computer operating system that allows peripheral devices to communicate directly with the computer memory without going via the central processor or CPU.

DOS — Disk Operating System. Part of the operating system of PC and PC compatible computers

Driver — A piece of software that handles communications between the main program and a hardware peripheral, such as a soundcard, printer or scanner. Also a term used to refer to a physical loudspeaker drive unit — eg bass driver.

Endian (Little and Big): Little and Big Endian describe the ordering of multi-byte data that is used by a computers microprocessor. Little Endian specifies that data is stored in a low-to-high byte format; this ordering is used by the Intel microprocessors. Big Endian specifies that data is stored in a high-to-low byte format; this ordering is used by the Motorola microprocessors.

Format — A procedure required to ready a computer disk or digital tape for use. Formatting organises the medium into a series of ‘electronic pigeon holes’ into which data can be stored. Different computers often use different formatting systems.

Fragmentation (cf. defragment) — The process by which the available space on a disk drive gets split up into small, sometimes unusable, sections due to the storing and erasing of files.

GUI — Graphical User Interface (pronounced ‘Gooey’). A software program designer’s way of creating an intuitive visual operating environment controlled by a mouse-driven pointer or similar.

IRQ — Interrupt Request. Part of the operating system of a computer that allows a connected device to request attention from the processor in order to transfer data to it or from it.

Media Control Interface (MCI): A standard way for Windows programs to communicate with multimedia devices such as sound cards and CD players. If a device has an MCI device driver, it can easily be controlled by most multimedia Windows software.

Microsoft Sound Mapper: The Sound Mapper is a special device that attempts to select the most appropriate sound card (map) on which to play a sound, or it will translate the sound into a format that can be played on your sound card.

Object Linking and Embedding (OLE): OLE is a technology developed by Microsoft to allow independent applications to behave as though they are tightly integrated. This allows objects such as audio files to be integrated into other applications such as a Microsoft Word document.

Real-Time Streaming Protocol (RTSP): A proposed standard for controlling broadcast of streaming media. RTSP was submitted by a body of companies including RealNetworks and Netscape.

Redirector File: A metafile that provides information to a media player about streaming media files. To start a streaming media presentation, a Web page will include a link to a redirector file. Linking to a redirector file allows a file to stream; if you link to the media file, it will be downloaded before playback begins. Windows Media redirector files use the .asx or .wax extension.

Windows Media Format: Microsoft's Windows Media file format that can handle audio and video presentations and other data such as scripts, URL flips, images and HTML tags.