John Cletheroe's
PC And Internet Hints

PC And Internet Glossary - Including File Extensions - V

V.21

The standard for full-duplex communication at 300 baud.

V.22

The standard for half-duplex communication at 1200 bps.

V.22bis

The standard for full-duplex modems sending and receiving data across telephone lines at 1200 or 2400 bps.

V.29

The standard for half-duplex modems sending and receiving data across telephone lines at 1200, 2400, 4800, or 9600 bps. This is the protocol used by fax modems.

V.32

The standard for full-duplex modems sending and receiving data across phone lines at 4800 or 9600 bps. V.32 modems automatically adjust their transmission speeds based on the quality of the lines.

V.32bis

The V.32 protocol extended to speeds of 7200, 12,000 and 14,400 bps.

V.34

The standard for full-duplex modems sending and receiving data across phone lines at up to 28,800 bps. V.34 modems automatically adjust their transmission speeds based on the quality of the lines.

V.42

An error-detection standard for high-speed modems. V.42 can be used with digital telephone networks. MNP is an alternative standard which performs a similar task. V.42 contains LAPM (Link Access Protocol - Modems) and MNP 1-4. When two V.42 compliant modems establish a connection, they use LAPM to control data errors and retransmit bad data blocks. If one modem supports V.42 and the other only supports MNP then the two negotiate to use MNP. In both cases the error control process is automatic and requires no special user actions or software.

V.42bis

A data compression protocol that can enable modems to achieve a data transfer rate of 34,000 bps. V.42bis roughly corresponds to MNP Level 5, the difference being in the amount of data compression. V.42 can usually generate a 4:1 ratio of data compression, depending on the type of file being transmitted. Data in files which are already compressed, such as PKZIP, GIF and JPG files, is unlikely to be compressed further by the modem's data compression system.

V.44

A data compression protocol, claimed to be superior to V.42bis especially for web page HTM files. V.44 might be closely related to V.92.

V.90

A high-speed protocol standard for modems. The open V.90 standard is the successor to the mutually incompatible proprietary X2 and K56Plus protocols. In theory all three of these protocols are capable of 56.6kbps; in practice performance depends on the quality of the connection and you should be very grateful if you regularly get better than 40kbps.

V.92

A high-speed protocol standard for modems. I believe V.92 is a slightly modified form of V.90.

VB

Visual BASIC. See BASIC.
File extension. VBScript file.
File extension. Visual BASIC .NET assembly information file.
File extension. Visual BASIC .NET class.
File extension. Visual BASIC .NET code file.
File extension. Visual BASIC .NET COM class.
File extension. Visual BASIC .NET component class.
File extension. Visual BASIC .NET custom control.
File extension. Visual BASIC .NET data form wizard.
File extension. Visual BASIC .NET inherited form.
File extension. Visual BASIC .NET inherited user control.
File extension. Visual BASIC .NET installer class.
File extension. Visual BASIC .NET module.
File extension. Visual BASIC .NET Transactional component.
File extension. Visual BASIC .NET user control.
File extension. Visual BASIC .NET web custom control.
File extension. Visual BASIC .NET web form.
File extension. Visual BASIC .NET web service.
File extension. Visual BASIC .NET Windows form.
File extension. Visual BASIC .NET Windows service.

VB40016.DLL and VB40032.DLL

See "Visual BASIC Runtime Library Files".

VBA

Visual BASIC For Applications. See BASIC.

VBD

File extension. ActiveX document state file. I do not know if VBD files can contain viruses or not.

VBE

File extension. VBScript Encoded script file. VBE files can contain viruses.

VBG

File extension. Visual BASIC group project file. I do not know if VBG files can contain viruses or not.

VBL

File extension. Visual BASIC V6 Control licensing file. I do not know if VBL files can contain viruses or not.

VBP

File extension. Visual BASIC Project. A file associated with a Visual BASIC V6 program. I think this file holds a list of the modules and forms which comprise the program. I think the same information is held in a MAK file in previous versions Visual BASIC, possibly in a different format. I do not know if VBP files can contain viruses or not.

VBR

File extension. Visual BASIC V6 Remote Automation registration file. I do not know if VBR files can contain viruses or not.

VBRUN100.DLL and VBRUN300.DLL

See "Visual BASIC Runtime Library Files".

VBS

File extension. Visual BASIC Script program file. VBS files can contain viruses.

VBScript

Visual BASIC Script. See BASIC.

VBW

VFile extension. Visual BASIC Workspace. A file associated with a Visual BASIC program. I do not know if VBW files can contain viruses or not.

VBX

File extension. Visual BASIC Extension (?). Visual BASIC Custom Control (for versions of Visual BASIC prior to V6). Each VBX file adds an additional type of control (object) to the Visual BASIC language. In Visual BASIC V6 the custom controls are OCX files.

VBZ

File extension. Visual BASIC V6 Wizard launch file. I do not know if VBZ files can contain viruses or not.

VCD

A virtual CD file, created by and used by the VirtualDrive program (published by Farstone). Since VCD files are images of CD's, they can contain viruses.

VCF

File extension. vCards (also called Business Cards), which can be used to store additional information about "contacts" (entries in the Outlook Express or Outlook address books). I do not know if VCF files can contain viruses or not.

VDEF

In Windows, the file system driver for unformatted disk drives.

VDM

Virtual DOS Machine. The equivalent of the MS-DOS Prompt in previous versions of Windows. Invoked by means of Start > Run > CMD, or automatically when a DOS program or batch file is run.
File extension. VDM Play file or Vedit file. Purpose unknown.

Vector font

A font in which the shapes of the characters are specified as lines and curves. Ideal for x/y plotters.

Veronica

A method of searching the Internet used prior to the introduction of search engines. Most Internet users nowadays will have no use for Veronica.

Version Number

Traditionally, each new major version of a commercial program was given a version number such as 1.0, 2.0, 3.0 and so on in sequence.

Bug fix releases (patches, or "service releases" in Microsoft jargon) were given version numbers such as 1.01, 1.02, 1.03, etc. Some companies used numbers such as 1.10, 1.20, 1.30, etc.

Some authors use a version number of 0.xx to indicate a pre-release test version of a program.

Microsoft, being Microsoft, have gone their own way with version numbering. Modern Microsoft programs often have external version numbers such as Word 97, an internal version number, often with four or five parts, and also a build number (see that entry). Often the various methods of reporting these numbers give inconsistent results. Sometimes version numbers are allocated out of sequence so as to leapfrog a competing program's version numbering.

Opinion: Perhaps Microsoft's confusion with version numbering is a deliberate marketing policy in an attempt to pretend that their products have no bugs. Perhaps it is merely incompetence and lack of organisation. Either way, if Microsoft can't get a simple thing such as version numbering right, it gives little hope that the more technical aspects of software development are likely to be carried out reliably.

Vertical Bar

| (see that entry).

VESA

Video Electronics Standards Association. A video system used by some old DOS games. Generally a pain.

VFAT

In Windows, the file system driver for floppy disk drives, hard disks, and Flash File Systems.

VFW (or VfW)

Video For Windows. Roughly, the Microsoft equivalent of Apple's QuickTime - software for playing sound and video files.

VGARTD.VXD

A virtual memory manager for AGP video boards, required for their DIME (Direct Memory Execute) feature. GART stands for Graphics Address Remapping Table.

VGX

Variational Graphics Extended. I do not know if this is the general meaning of VGX, or a specific meaning assigned by a particular company.

Video CD

A Video CD can hold up to 74 or 80 minutes of video on a standard 650MB or 700 MB CD. However, Video CD's compromise considerably on quality to fit the data into the small amount of space compared to DVD's. Super Video CD's use near-DVD-quality video encoding, about twice as good as Video CD's, but can only hold 35 or 45 minutes of video.

View

In modern database programs a view can be thought of as a virtual file, constructed by the program "on the fly" from one or more fields and one or more records taken from one or more physical files. To the user, the view acts in every respect as if it were a real file, subject to any restrictions which may be imposed by the programmer, potentially allowing searching, viewing, input, deletion and editing of its records. A "dynaset" is the same as a view. Presumably "dynaset" is a contraction of "dynamic set". The Microsoft Access database program uses the word "query" for the same idea. Technically, I believe that a query defines what is selected and a dynaset is the result of a query.

Viewpoint Media Player

A potentially malicious adware/spyware program surreptitiously installed as part of some versions of AOL software. It can be uninstalled using an option in Control Panel > Add/Remove Programs. It serves no purpose to the user as all its functions can be performed by standard Windows components.

Virtual Machine

Software which simulates a real or hypothetical computer processor, so allowing programs written for that processor to be run on another type of computer. The term is used for emulators (programs which make one computer appear to be another computer) and also for software which runs programs written in the Java programming language, so allowing such programs to be run on any physical computer and with any operating system. By the way, I suspect that the JavaScript language does not use the virtual machine concept.

Microsoft often use the terms "Virtual Machine" or "VM" to mean Java Virtual Machine because their marketing people cannot bring themselves to utter the word "Java", the language having been created by another company.

To add to the confusion, the runtime files for compiled Visual BASIC 5 and Visual BASIC 6 programs are called MSVBVM50.DLL and MSVBVM60.DLL - Microsoft Visual BASIC Virtual Machine V5 and V6.

Virtual Memory

The use of part of a hard disk drive to simulate RAM, using a swap file (also called a paging file).

Virus

A malicious piece of coding hidden inside a program or similar file, which spreads and replicates itself automatically. Viruses range from harmless, merely displaying a humorous message, to extremely harmful, corrupting or deleting data on your computer.

Visual BASIC

See BASIC.

Visual BASIC For Applications

See BASIC.

Visual BASIC Runtime Library Files

Compiled Visual BASIC programs need the appropriate runtime library file to be present on a computer in order to run. Each version of Visual BASIC has a corresponding runtime library file. If a program was compiled with a particular version of Visual BASIC then that version of the runtime library file will be required. Individual programs may also require the presence of files associated with custom controls (ActiveX controls) and their own configuration settings and data files.

Runtime library files are often distributed with compiled Visual BASIC programs. Program installation routines may install these to a sub-folder of C:\Windows or to the program's own target folder (where its EXE file and any other files are held). Only one copy of each runtime library file is required, best held in C:\Windows\System. In most cases various "builds" (sub-versions) of each file have been released; keep the latest.

The runtime library files for some versions of Visual BASIC are:

Visual BASIC V1: VBRUN100.DLL
Visual BASIC V3: VBRUN300.DLL
Visual BASIC V4 (for 16-bit programs, for Windows V3.1 and earlier): VB40016.DLL
Visual BASIC V4 (for 32-bit programs, for Windows 95 and later): VB40032.DLL
Visual BASIC V4 programs may also require VB4EN16.DLL and/or VBDB16.DLL
Visual BASIC V5: MSVBVM50.DLL (Microsoft Visual BASIC Virtual Machine, V5.0)
Visual BASIC V6: MSVBVM60.DLL (Microsoft Visual BASIC Virtual Machine, V6.0)

Please note that I am unable to supply copies of any of these files, both for copyright reasons and because of the large sizes of the files for modern versions of Visual BASIC. The files are widely available on the Internet and any search for their filenames should quickly locate plenty of possible sources.

Visual BASIC Script

See BASIC.

Visual BASIC Scripting Edition

See BASIC.

Visual Studio

A collection of Microsoft programming language development software, comprising:

Visual Basic (an object oriented version of Basic in which programs can be created that run under Windows)
Visual C++ (a version of C, the machine code-like programming language)
Visual FoxPro (a database programming language, I think)
Visual InterDev
Visual J++ (a dialect of Java, the object oriented programming language)
Visual SourceSafe

Visual Studio is sold as a complete package, and in addition each programming language can be purchased separately. There are several editions of some of the languages, with more or less features.

VIVO

In the descriptions of video boards, this means video in, video out. In other words, the card can accept a video input from a suitable device (a digital camcorder, presumably), and can output to a television (probably as an S-Video signal).

VKD

Virtual Keyboard Device Driver.

VM

Virtual Machine - see that entry.
Virtual Memory. The use by an operating system of an area of a hard disk to simulate memory, when there is insufficient actual memory. Also called a swap file. Often used to hold information about programs which are temporarily dormant, or "swapped out".

VML

Vector Markup Language.

VOB

File extension. DVD Video Movie File.

VoIP

Voice Over Internet Protocol, or Voice On Internet Protocol. The simulation of voice telephone calls using the Internet as the transmission medium. Not feasible on a modem connection but an interesting concept for those with broadband. However, in Britain VoIP will not get round the scandal of the BT monopoly and rip-off on line rental.

Volume

The loudness of sound, or the control which adjusts this.
The amount of traffic, for example on a network.
An item of exchangeable media, for example a floppy disk or a CD. A volume label is a short name given to a disk and held on it in electronic form. Volume labels are usually displayed in Windows Explorer when a disk is in the drive. However, there is a bug in Windows XP which prevents the volume label information being updated when one CD is removed and another inserted.

Vorbis

See OGG.

VPN

Virtual Private Network. I think this a network which operates over the Internet but which has (in theory) its use tightly restricted to a set of users, so as to appear to them as if it were a private network.

vpowerd

Sometimes spuriously listed as having failed to load in Bootlog.txt. See Microsoft KnowledgeBase article 127970 for details of the various misleading spurious error messages which can appear in Bootlog.txt.

VREDIR

In Windows, the file system driver for network drives mapped by the Client for Microsoft Networks.

VRML

Virtual Reality Modelling Language. As with HTML, VRML files are ASCII text files but with VRML language tags in angle brackets instead of HTML tags. VRML files have the extension WRL ("world").

The two versions of the VRML language use completely incompatible commands and therefore it is vital to check that you have a VTML program or plug-in which is compatible with a particular VRML file. Files for both versions of the language have the extension WRL - not a clever idea.

vserver.vxd

vshare

VXD

File extension. Virtual Device Driver.

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Most recently modified 21-Apr-07