John Cletheroe's
PC And Internet Hints

PC And Internet Glossary - Including File Extensions - R

RA

File extension. RealAudio file. A type of sound file associated with the RealAudio program. I do not know whether RA files can contain viruses or not; it seems unlikely.

RAD

Rapid Application Development.

Comment: The creation of computer systems with no design, analysis, user involvement or testing. As you would expect, the results are awful. Knocking such a system into something acceptable is usually more costly and time consuming than throwing it away, starting again and doing the job properly.

RAID

Redundant Array of Inexpensive Disks. A system used by some servers. If one disk fails it can be removed and replaced without the system having to be brought down. Additional disks can be added to the system as required for more storage capacity.

RAM

  1. Random Access Memory.

  2. File extension. RealAudio file. A type of sound file associated with the RealAudio program. I do not know whether RAM files can contain viruses or not; it seems unlikely.

RAM Specifications, RAM Timings

See "CL Numbers", "DDR Numbers" and "PC Numbers".

Ranged

A term often used in RPG's (role-playing games). Long distance combat, and weapons such as bows and arrows which are used in long distance combat. See also Melee.

RAR

An archive file format, similar to ZIP. The contents of RAR archive files can be extracted using the "Unzip Them All" utility, which is available via http://www.bykeyword.com or downloaded directly from http://www.herve-thouzard.com/unzinst.exe (both external links verified Jun-04).

RAS

Remote Access Service (or Services?). Appears to be associated with a list of telephone numbers maintained in Windows, although there may be more to it than that.

Raster Font

Same as bitmapped font. A font in which the shapes of the characters are specified as dots in a rectangular grid. A fast but very primitive method, ideal for monitors and dot-matrix printers.

RAT

File extension. Ratings file. A file associated with Microsoft Internet Explorer's Content Advisor facility, which can control which web sites a user can access, for example to prevent young children accessing inappropriate material. Ratings are supplied by RSACi (Recreational Software Advisory Council on the Internet). I do not know whether RAT files can contain viruses or not; it seems unlikely.

RBK

Backup copies of the Registry, created by the Configuration Backup Tool program in Windows 95. See Microsoft KnowledgeBase article 135120 for full details. These files are automatically compressed by the Configuration Backup Tool program. These files have filenames of the format REGBACKn.rbk, where n is a digit from 1 to 9. They are created in the C:\Windows folder. If you use the Configuration Backup Tool program, be prepared for a lengthy delay near the end of the backup operation and an extremely lengthy delay near the end of the restoration operation. I do not know whether RBK files can contain viruses or not; it seems unlikely.

RBL

Real-time Blackhole List. An email anti-spamming system which runs on the server. Often deletes messages which it shouldn't.

RC

Release Candidate. Microsoft jargon for a beta release, in other words a test version of a program.

RDF

Resource Description Framework. A method of describing a web site's metadata (information about the content of a web site).

RDO:

Microsoft KnowledgeBase article title prefix for articles relating to Remote Data Object, which I would guess is a method of accessing information in database files on another computer over a network.

RDS

Remote Data Service. Related to ADO, DAO, MDAC, ODBC, etc. Microsoft KnowledgeBase article 190463 has some information on RDS and related subjects.

Re:

Reply. A prefix in front of the subject of an email message indicating that it is a reply.

README.TXT, READ.ME, etc

A file, usually an ASCII text file, giving either vital instructions for installing, configuring, using or registering a program, or technical hints not included in the program's printed manual or its online help. Such files are always work a quick scan through in case they include anything important, although often they contain deeply technical material. To view as README file, open it in Notepad, Write, WordPad or Word, etc. If the extension is .ME then you will need to changed the "Open Files Of Type" to "All files (*.)" in order to list the file in the FILE > OPEN dialog box.

Real Audio

A program used to play sound files. The program can also play streaming data transferred over the Internet. As far as I know there is no method within the program of saving the audio file currently being played, which is a serious disadvantage. Depending on how the link to the audio file is configured, it may be possible to save the file on the associated web page.

Recursion

See "Recursion". :)

Red Book

See "Book".

Red Hat

A version of the Linux operating system.

Redistributable, Redistributable Package, Redistribution

These terms are never defined but they seem to refer to the inclusion of software components published by another company (such as Microsoft) with a program, that are required in order to make that program operate. A good example would be the inclusion of a version of Microsoft DirectX with many modern games programs. MDAC (Microsoft Data Access Components) is another example, as are many DLL files, Visual BASIC custom controls and ActiveX controls. As well as the legal minefield associated with these software components, there are also horrendous technical problems associated with the various combinations of the multitude of versions of them. The entire system is a house of cards, where disturbing one component will often cause the entire structure to collapse. Many users and support staff have spent vast amounts of time attempting to resolve these problems and a better fundamental design concept is urgently required.

REG

File extension. Registration entries. REG files can contain instructions which could perform undesirable operations on a computer.

Regina

See "Rexx and Regina".

Register

  1. A one byte unit of storage in a processor or memory, etc.

  2. To inform a commercial program's publisher that you have purchased it, in theory so that they can inform you of updates, bug fixes, etc but in practice registration usually just results in you receiving more junk mail and serves no useful purpose as far as the user is concerned.

  3. To inform a shareware author that you have downloaded or otherwise obtained their program and wish to retain it and make regular use of it, and therefore wish to make a payment to them for that. Registration is always optional but in many cases shareware programs have nag screens, restricted facilities (such as a limit on the size of data files or being unable to save or print files) or an automatic expiration period after which the program will not work. Registering often entitles you to an enhanced or later version of the program, and/or to receive information about problems, and/or technical assistance. Making payments to authors in another country is a problem, of course.

Registry

A set of system files used by Windows 95 to store various configuration information. Modern programs tend to use the Registry to store their configuration settings instead of the traditional INI file system. Associations between file extensions (file types) and programs are now also stored in the Registry. The Registry physically consists of two files which are usually very large. Only experts should change Registry information manually.

RegWorm

Registration Worm. An undesirable feature of software, which involves an over-complex procedure to be followed before the program can be used. An example is Microsoft's Windows Product Activation feature. Closely associated with DRM (Digital Rights Management) and copyright protection. Some RegWorms can make a program so awkward to use, even if you have a legitimate copy, that it becomes worthless.

Relational Database

A database program in which two or more related files can be open at once.

Relationship

See "Join".

Remote Desktop

A feature of Windows XP (Professional Edition only) which allows you access files and programs on your computer from another computer via the Internet.

Repository

A copy of a library held on a server, from which developers can download modifications and additions. See also "CVS".

The word repository might have additional meanings, probably minor variants on the same principle.

RES

File extension. Visual BASIC V6 Resource file. I think resource files hold the wording for menus, dialog boxes, etc, allowing them to be easily changed into another language (French, Spanish, German, etc). I do not know whether RES files can contain viruses or not; it seems unlikely.

RESX

File extension. Assembly Resource File (in .NET).

Return Key

In most situations the Enter key on the numeric keypad performs exactly the same operation as the Return key on the main part of the keyboard.

The Return key is occasionally called the Newline (or New Line) key.

Pressing the Return key in a Windows dialog box does not move the cursor to the next field. Instead, it is almost always equivalent to clicking the OK button. Users familiar with the concept of pressing the Return key after each field take a long time to get used to this aspect of Windows' design. To move the cursor to the next field in a Windows dialog box, press the TAB key. To move to the previous field, press SHIFT/Tab. To move to any other field, click on it with the mouse.

In a Word processing program, do not press the Return key at the end of each line but only between paragraphs. Let the program automatically handle the line breaks and word wrapping between lines within each paragraph.

Rexx and Regina

Rexx is a very obscure programming language, designed to teach programming to beginners. Regina is an interpreter for Rexx. Two far more obvious programming language choices for beginners are BASIC and LOGO.

RFC

Request For Comments. A series of documents which describe technical details of the Internet, its protocols, software, commands used in programs, etc. each document has the prefix RFC followed by a number. RFC's are widely available on the Internet. The name is very confusing since RFC's are documents describing established Internet standards, not tentative proposals being put up for discussion.

RFE

Request For Enhancement. A piece of jargon used by Sun when referring to requests from users to add features to Java. Also used in the Open Source/Java/Linux world (for example, on the SourceForge.net web site) to refer to any requests from users for improvements to programs.

RFID

Radio Frequency Identification. A system for tracking items through the distribution and delivery process using electronic tags. The tags themselves cost about 15 US cents each. The cost of the equipment which writes and reads them, and the development of the computer systems which keep track of items, is rather more significant. Albertson's, Target and Wal-Mart all intend to make the use of RFID tags compulsory for its major suppliers in the relatively near future.

RGB

Specifying a colour in terms of the intensity of its red, green and blue components. See "Hex".

RIAA

Recording Industry Association of America. A body of record companies and similar organisations, which attempts to protect the copyright of audio and video media (CD's, DVD's, etc).

Right Click

To click the right mouse button. Right clicking often invokes a menu of operations which can be performed on the clicked object. In Windows 95 right clicking often leads to the object's configuration or properties options.

Right Delete Key

Either of the two keys marked "Del" or "Delete". Pressing either right delete key deletes the character to the right of the cursor and closes the gap that would otherwise be created. If a section of text or one or more objects are selected, pressing either right delete key or the left delete key will delete whatever is selected. See also "Left Delete".

Ring

See "Web Ring".

Ripper

See "DAC".

Riven

The sequel to Myst (see that entry).

RJ11

A standard type of connector used in Britain for domestic ADSL broadband connections. ADSL filters have RJ11 sockets for connections to ADSL modems and routers, which in turn have cables terminating in RJ11 plugs.

RJ11 plugs are usually made of transparent plastic and click into position. To remove the plug, a small plastic clip must be pressed.

An RJ11 connector has space for up to six conductors in six parallel channels but some spaces may not be used.

RJ11 plugs and sockets may be used in other countries for other purposes. For example, I believe RJ11 connectors are used for normal telephones in the USA.

It would appear that the connectors to the telephone line on dial-up modems, both internal and external, are RJ11 sockets. The same seems to also be true of broadband modems and routers. However, I have not researched this extensively.

British domestic normal phone connections are BS6312 plugs and sockets, which are different to RJ11.

RJ45

A standard design of connector used on Ethernet network interface cards. Ethernet connections on modern personal computers, modems and routers are RJ45 sockets. Ethernet cables terminate with RJ45 plugs. RJ45 plugs are usually made of transparent plastic and click into position. To remove the plug, a small plastic clip must be pressed.

An RJ45 connector has space for up to eight conductors in eight parallel channels but some spaces may not be used.

BS6312, RJ11 and RJ45 are all different to each other. I believe it may be physically possible to insert an RJ11 plug into an RJ45 socket but the consequences of doing so may be dire.

RLE

Run-length encoding. A relatively unsophisticated method of data compression. In simple terms, the data is encoded by specifying how many one's or noughts are transmitted (or stored) together, for example "six ones", "fourteen zeros", etc. Obviously this achieves a good compression ratio for data which has long runs of consecutive one's or noughts. I suspect that this system is used at the byte level in GIF files, for example "ninety-five 178's". This would explain why GIF files are good for graphics with large areas of identical colours but poor for photographs. In practice more advanced techniques are used in conjunction with the simple algorithm described here.

RM

  1. File extension. RealAudio file. A type of sound file associated with the RealAudio program. I do not know whether RM files can contain viruses or not; it seems unlikely.

  2. Research Machines. A UK computer manufacturer which in the past largely concentrated on the school market. With the near universal adoption of Intel processors (or clones thereof) running Microsoft Windows, I believe that the company has now switched so as to concentrate on manufacturing digital television decoders.

RMA

Return Merchandise Authorisation. Authorisation from a manufacturer to return a faulty device to them for repair, replacement, refund, etc. In many cases manufacturers will only issue an RMA once they have been confinced that the device actually is faulty. In Britain, if the faulty device is still under guarantee then the purchaser should initially contact the retailer, not the manufacturer. However, there is nothing to stop them contacting the manufacturer for advice, especially if it is not certain whether the problem might be caused by some other factor such as incorrect configuration or another device. The RMA term is also sometimes used to refer to actual process of returning a defective device.

RMI

File extension. According to one source, a type of MIDI sound file. I do not know whether RMI files can contain viruses or not; it seems unlikely.

RMM

File extension. A type of file associated with the RealAudio program. I do not know whether RMM files can contain viruses or not.

RMS

  1. Rights Management Services. A proposed feature in future version of Windows which will control what a user can do with a file (open, edit, delete, copy, etc). This appears to be an extension of the Access Control List concept.

  2. Root mean square. A term often used in the context of sinusoidal waveforms (sine waves), for example with audio amplifiers and speakers, and alternating current mains electricity.

RNAAPP

Remote Network Access Application. A component of Dial-Up Networking for Windows. After an online session, the RNAAPP task is not immediately shut down, which may cause programs such as Word to crash due presumably to a file or disk locking problem. It may help to invoke the Task List (by pressing CTRL/ALT/DEL) and shutting down RNAAPP (several attempts may be required). I suspect there may be some other factor present on my computer which causes this problem to occur far more frequently than normal.

RO or R/O

Read Only. An attribute of a file which when set prevents the file from being deleted or modified. The file can still be copied and read.

Root

The top-level directory of a disk. By extension, and somewhat loosely, the top level of any directory tree, for example C:\My Documents could be said to be the root of the area used to store your files.

Rootkit

A particularly nasty form of computer malware. A rootkit can hide itself and its associated files from almost all means of detection. Recently (Nov-05) Sony issued audio CD's which install a rootkit on PC's they are played on, ostensibly as a copyright protection system. The company has quite rightly attracted an enormous amount of adverse publicity as a result.

RoundCube

A browser-based webmail program for use on servers.

ROT-13

A simple encryption system.

ROTFL

Roll on the floor laughing.

Roxio

A publisher of CD burning software. Adaptec were taken over by Roxio, who in turn have been taken over by Sonic.

RPC

Remote Procedure Call. A protocol in Windows which allows a program running on one computer to access another computer. As you would expect, RPC has been the subject of a seemingly endless flood of Microsoft security alerts and patches.

RPG

  1. Report Program Generator. A programming language which, as its name suggests, is mainly intended for writing programs which print reports from files or databases.

  2. Rocket Propelled Grenade. Although this is obviously not a computer related meaning, it might be used in some military games.

  3. Role-playing Game. A type of game, which need not necessarily be played on a computer, involving frequent simulated fighting and sometimes a little simple puzzle solving, usually in a fantasy or science fiction scenario. In most cases the games includes a complicated system with factors such as XP (experience points) and HP (hits points). Dungeons and Dragons is the best known example; there are many more.

RPT

  1. File extension. Report.

  2. File extension. Crystal Report, which according to one source is "a file that publishes data to a Windows form". Something to do with .NET.

RRD

Removable Rigid Disk. A new type of backup medium, announced by Iomega in Nov-03. RRD cartridges will consist of sealed hard disk units, complete with read/write heads and motor. They will hold up to 35GB. The drive will fit in a standard 3.5" floppy disk drive bay. RRD drives are expected to cost about $349 (£210 at normal exchange rates or £349 at electronic products exchange rates), with each 35GB cartridge costing under $49 (£29).

RRGGBB

The three components of a colour: red, green and blue, as six hex digits. In hex, the digits are 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, A, B, C, D, E and F. Some examples:

RS-232

The standard for the signals, voltages, pins, protocols, etc used on a PC's COM ports (COM1:, COM2, etc). Nowadays the use of RS-232 (and therefore the COM ports) is largely restricted to the connection between a PC and an external modem.

RSA

The most commonly used form of public key encryption. From the initials of the last names of its three developers: Ronald Rivest, Adi Shamir and Leonard Adelman.

RSACi

See "RAT".

RSS

  1. Rich Site Summary, RDF Site Summary or Really Simple Syndication (sources vary). A method of automatically displaying text information from a user-specified set of different Internet sources, all on one page. As far as I know the text is unformatted except for links and images. In practice the use of images is rare.

    RSS provides a means of obtaining access to email newsletters which would otherwise be mistakenly blocked as spam by the end-user's ISP, or by a spam-blocking program on their computer. Special software is required to both to create and to view RSS information. RSS is an XML format.

    RSS client programs, which display the information on the end-user's computer, are called aggregators, news aggregators, or feed readers. One such program suitable for all Win9x operating systems, including Windows 95, is Amphetadesk (external link verified Sep-03), which works in conjunction with the user's default web browser program. An alternative is SharpReader (external link verified Apr-04), which is a three-pane viewer that allows you to filter out previously read items. SharpReader requires Microsoft's .NET Framework to be installed, which involves a 24MB download.

    RSS FAQ

  2. File extension. A file which contains an RSS feed as described above. RSS files can also have an extension of XML. I do not know whether RSS files can contain viruses or not.

  3. In Microsoft terminology, Remote Storage Server.

RSVP

Resource Reservation Protocol. An obscure internal Internet protocol.

RTC

Real Time Clock.

RTF

File extension. Rich Text Format. A file format for text which preserves some but not all formatting. RTF is sometimes useful as an intermediate stage when transferring a document file between two incompatible programs. It can also be used as a publishing medium, although Adobe Acrobat is much more popular.

RTFM

An invitation for a user to kindly consult the printed documentation which accompanied the product: Read the flaming manual!

RTM

Released To Manufacture. Microsoft jargon for a post-beta version of a program, deemed fit for sale.

RTS

Real Time Strategy. A type of computer game. The term is often used to describe a military game which is not turn-based, in which you command various troops and deploy various types of equipment.

RTS/CTS

Ready To Send/Clear To Send. A method of controlling the flow of information between two devices over an RS-232 connection. Special wires connect pins on the RS-232 connectors at each end and signals sent on these wires control the data flow. Using RTS/CTS is highly reliable but the cable must have the additional wires. All cables connecting PC's to external modems use the RTS/CTS system. See also "XON/XOFF".

RTSP

Real Time Streaming Protocol.

RVN

File extension. Riven saved game file.
Introduction

Punctuation A B C D E F G H I J K L M N O P Q R S T U V W X Y Z

PC and Internet Hints

Overall Site Home Page

About this personal web site JohnCletheroe

EMail me

Most recently modified 3-May-09