Appendix Glossary V

In the left margin you will find links to the glossary categorised alphabetically. Some of the pages are quite long and may take a few moments to load if you use a modem. This glossary is always being updated.

Glossary - V

V.I.S. - The visible image surface area of a monitor.

Vaporware - A term used to describe a piece of software that doesn't exist, is suspected not to exist, or is incapable of performing as promised. It is not uncommon for a software corporation to make fantastic promises as to the functionality of an upcoming software release that ultimately prove to be undeliverable. In the software industry, there is often something of a yin/yang relationship between marketing efforts and technical capabilities. They can't exist without each other, but that doesn't stop them from trying from time to time.

Vector Graphics - In contrast to a bitmap, which is figuratively a stored snapshot of a graphic that contains a fixed number of pixels, a type of image that is more versatile in that it can be sized without encountering distortion. Additionally, vector images display better on computer monitors.

Veronica - A search engine for searching Gopher sites using keyword searching.

VESA Local Bus - (VL-Bus) A 32-bit local bus that runs between the CPU and peripheral devices at speeds up to 40MHz.

VGA - This means Video Graphic Array. This is the current top of the line graphic system. It offers you stunning colour graphics, great resolution and crisp text. SVGA or Super VGA expands the abilities of the VGA!

VHS - "Video Home System" The lack of cleverness evident in the name for the current consumer videotape standard is a perfect match for the lack of image quality attainable within this tape medium. Of all the different tape formats that have been introduced over the years (nearly all of which are superior in quality), VHS was the one that was accepted as the universal standard for distribution of video content to end users. Marketing superiority often takes precedence over technical superiority, and never has this been more evident that in the case of the ubiquity of VHS devices.

Video - The transmission of moving pictures or animation to a monitor or television. In a broader sense, any text or images transmitted from a computer and displayed on a display monitor or television. Video images may be broadcast live, filmed, or video-recorded and stored on tape or disk.

Video Adapter - Sometimes called video card, a plug-in circuit board that gives a computer video display capabilities. The ability of a computer to produce video will depend not only on the adapter but the monitor as well. Most video cards contain some memory so the computer's RAM is not called upon to store images. A video adapter allows the computer to display both text and graphics in a choice of resolutions and colour depth.

Video Capture - The act of recording the contents of a video tape into a digital file. If the material to be captured is a single frame of a videotape, then the resulting data can be stored in a single image file, such as a TIFF or PICT file. This is sometimes called a "frame grab." In order to capture a motion segment of a video clip, one must store it in a digital video format such as QuickTime or AVI. A captured digital video clip can then be edited and played back on a computer without the benefit of a video tape device.

Video Card - This is the component of your computer that puts a picture onto your screen. They can also 'accelerate' motion video, and 3D games.

Video Conferencing - Using a computer, video camera, and network such as the Internet, to conduct a live conference between two or more people. Video conferencing is an extremely useful method of communication because it saves people the time and expense of travel and can often accomplish many of the things a physical meeting can. A two-person videoconference is known as point-to-point, while more than two people involved in a session is a multipoint conference.

Video Memory - The memory found in a video adapter that stores images as bitmaps before they are sent to the display monitor. Because displaying video images requires a great deal of computing speed and memory, the video adapter is equipped to handle this function rather than relying on the computer's CPU. There are several types of video memory such as VRAM and WRAM.

Virtual - An imaginary conceptualisation of something real. For example, many feel that the Internet is a virtual world unto itself. The term takes on many uses in the computer world as a wide variety of devices and software exist for the sole purpose of providing simulations of reality.

Virtual Channel Memory - (VCM) VCM is a memory architecture developed by NEC. VCM allows different blocks of memory-each with its own buffer-to interface separately with the controller. This way, system tasks can be assigned their own virtual channels. Information related to one function does not share buffer space with other tasks running simultaneously, thereby making overall operations much more efficient.

Virtual Memory - Simulated memory. When RAM is full, the computer swaps data to the hard disk and back as needed.

Virtual Private Network - (VPN) VPN is Microsoft's implementation of Point-to-Point Tunnelling Protocol (PPTP), a protocol that provides a secure connection via the Internet. Virtual Private Networks allow computers to use the public Internet backbone as a channel for private data communication. With encryption and encapsulation technology, a VPN creates a private passageway through the Internet. VPNs allow remote offices, company road warriors, and even businesses' customers to use the Internet, rather than pricey private lines, to reach company networks.

Virtual Private Network Adapter - VPN Adapter is the device set-up in Microsoft networking (Windows 95/98 or Windows NT) that provides services for a Virtual Private Network. In most cases, it is a dial-up adapter (or modem) configured specifically for the VPN.

Virus - A computer virus is a computer program that infects other computer programs and reproduces itself without the knowledge of the PC user. A virus may be destructive, and should never be ignored. Contrary to popular belief, not all viruses are dedicated to performing overt harm on computers that they inhabit. The vast majority of viruses would never perform such fabled destructive behaviour as reformatting the hard drive or spiking the water cooler. There are some nasty ones, though. A virus is a clear example of an area in which it is better to give than to receive.

Visual Basic - A type of object-oriented programming language and environment developed by Microsoft for the Windows operating system. Visual Basic allows programmers to create applications quickly by writing code to accompany onscreen objects such as buttons and windows.

VLIW - Very Long Instruction Word. A microprocessor that packs many simple RISC-like instructions into a much longer internal instruction word format. A VLIW microprocessor will usually have execution units, capable of executing all of the instructions contained in the instruction word, in parallel.

Voice Coil - A fast and reliable actuator motor that works like a loudspeaker, with the force of a magnetic coil causing a proportionate movement of the head. Voice coil actuators are more durable than their stepper counterparts, since fewer parts are subject to daily stress and wear and also provide higher performance.

VR - A simulated three-dimensional environment, displayed in real time with interactive capabilities. VR applications have been developed for the World Wide Web, although the technology is still at an early stage.

VRAM - (Video Random-Access Memory) - Dual-ported (two separate data ports) memory typically on a video or graphics card. One port is dedicated to the CRT and refreshes and updates the image. The second port is for the CPU or graphics controller and changes the image data in memory.

VRML - "Virtual Reality Modelling Language" A data specification designed to display three dimensional objects and environments on the world wide web. The standard was introduced to allow a specially equipped web browser to process the code that defines the 3D objects and their behaviour instead of downloading pre-rendered graphics as image files. So far, VRML has yet to really catch on, but there are a fair number of websites dedicated to delivering rich three-dimensional versions of really exciting objects, like pencils and office chairs. If that's what you're into, then VRML is the stuff for you.