Appendix C: Glossary of Terms

The glossary definitions that follow are based on definitions from Wikipedia.

Bar Code

A bar code is a machine-readable representation of information in a visual format on a surface. Originally barcodes stored data in the widths and spacings of printed parallel lines, but today they also come in patterns of dots, concentric circles, and hidden within images. Barcodes can be read by optical scanners called barcode readers or scanned from an image by special software. Barcodes are widely used to implement Auto ID Data Capture (AIDC) systems that improve the speed and accuracy of computer data entry.

Cable Modem

A cable modem is a type of modem that provides access to a data signal sent over the cable television infrastructure. Cable modems are primarily used to deliver broadband Internet access, taking advantage of unused bandwidth on a cable television network.

Carriage Return

The carriage return (CR) is one of the control characters in ASCII code, Unicode or EBCDIC that commands a printer or other sort of display to move the position of the cursor to the first position on the same line. It was mostly used along with line feed, a move to the next line, while carriage return precedes line feed to indicate a new line.


The clipboard is a software program that is used for short-term storage of data as it is transferred between documents or applications, via copy and paste operations. It is most commonly a part of a GUI environment and is usually implemented as an anonymous, temporary block of memory that can be accessed from most or all programs within the environment.

Code 39

Code 39 (also known as “USS Code 39”, “Code 3/9”, “Code 3 of 9”, “USD-3”, “Alpha39”) is a bar code symbology that can encode uppercase letters (A through Z), digits (0 through 9) and a handful of special characters like the $ sign. The barcode itself does not contain a check digit (in contrast to—for instance—Code 128), but it can be considered self-checking by some, on the grounds that a single erroneously interpreted bar cannot generate another valid character. Possibly the most serious drawback of Code 39 is its low data density: It requires more space to encode data in Code 39 than, for example, in Code 128. This means that very small goods cannot be labeled with a Code 39 based barcode. However, Code 39 is still widely used and can be decoded with virtually any barcode reader.

Control Panel

Control Panel is a part of the Microsoft Windows graphical user interface which allows users to view and manipulate basic system settings and controls, such as adding hardware, adding and removing software, controlling user accounts, and changing accessibility options. Additional applets can be provided by third party software.


Cascading Style Sheets (CSS) is a stylesheet language used to describe the presentation of a document written in a markup language. Its most common application is to style web pages written in HTML and XHTML, but the language can be applied to any kind of XML document, including SVG and XUL. The CSS specifications are maintained by the World Wide Web Consortium (W3C).

Device Driver

A device driver, or a software driver, is a specific type of computer software, typically developed to allow interaction with hardware devices. This usually constitutes an interface for communicating with the device, through the specific computer bus or communications subsystem that the hardware is connected to, providing commands to and/or receiving data from the device, and on the other end, the requisite interfaces to the operating system and software applications.

Dialog Window

In graphical user interfaces, a dialog window is a special window, used in user interfaces to display information to the user, or to get a response if needed. They are so-called because they form a dialog between the computer and the user—either informing the user of something, or requesting input from the user, or both.


A domain name (also, a hostname) is the unique name by which a network attached device (which could consist of a computer, file server, network storage device, fax machine, copier, cable modem, etc.) is known on a network. The domain name is used to identify a particular host in various forms of electronic communication such as the World Wide Web, e-mail or Usenet.


DSL or xDSL, is a family of technologies that provide digital data transmission over the wires of a local telephone network. DSL originally stood for digital subscriber loop, although in recent years, many have adopted digital subscriber line as a more marketing-friendly term for the most popular version of consumer-ready DSL, ADSL.


Database Source Names, more commonly seen as the abbreviation, DSN, are data structures used to describe a connection to a database. This DSN will take the form of protocol: subprotocol: host: port: database so as to completely specify all parameters of the connection.


Encryption is the process of obscuring information to make it unreadable without special knowledge, sometimes referred to as scrambling. Encryption has been used to protect communications for centuries, but only organizations and individuals with an extraordinary need for secrecy had made use of it. In the mid-1970s, strong encryption emerged from the sole preserve of secretive government agencies into the public domain, and is now used in protecting widely-used systems, such as Internet e-commerce, mobile telephone networks and bank automatic teller machines.


The Electronic Signatures in Global and National Commerce Act, or ESIGN, is a United States federal law passed by the U.S. Congress on June 30, 2000 to facilitate the use of electronic records and signatures in interstate and foreign commerce by ensuring the validity and legal effect of contracts entered into electronically.


A firewall is an information technology (IT) security device which is configured to permit, deny or proxy data connections set and configured by the organization's security policy. Firewalls can either be hardware and/or software based.


FTP or File Transfer Protocol is used to connect two computers over the Internet so that the user of one computer can transfer files and perform file commands on the other computer.


In a communications network, a network node equipped for interfacing with another network that uses different protocols.


HTML, short for HyperText Markup Language, is the predominant markup language for the creation of web pages. It provides a means to describe the structure of text-based information in a document — by denoting certain text as headings, paragraphs, lists, and so on — and to supplement that text with interactive forms, embedded images, and other objects. HTML is written in the form of labels, created by greater-than signs (>) and less-than signs (<). HTML can also describe, to some degree, the appearance and semantics of a document, and can include embedded scripting language code which can affect the behavior of web browsers and other HTML processors.

IP Address

An IP address (Internet Protocol address) is a unique address that certain electronic devices use in order to identify and communicate with each other on a computer network utilizing the Internet Protocol standard (IP)—in simpler terms, a computer address. Any participating network device—including routers, computers, time-servers, printers, Internet fax machines, and some telephones—can have their own unique address. Also, many people can find personal information through IP addresses.


JavaScript is the name of Netscape Communications Corporation's and now the Mozilla Foundation's implementation of the ECMAScript standard, a scripting language based on the concept of prototype-based programming. The language is best known for its use in websites (as client-side JavaScript), but is also used to enable scripting access to objects embedded in other applications.


JPEG is a commonly used standard method of compression for photographic images. The name JPEG stands for Joint Photographic Experts Group, the name of the committee who created the standard.

Line Feed



A liquid crystal display (LCD) is a thin, flat display device made up of any number of color or monochrome pixels arrayed in front of a light source or reflector. It is prized by engineers because it uses very small amounts of electric power, and is therefore suitable for use in battery-powered electronic devices.

Local Area Network

local area network (LAN) is a computer network covering a small geographic area, like a home, office, or group of buildings. Current LANs are most likely to be based on Ethernet technology, running at 10 Mbps, 100 Mbps, or 1 Gbps, or on Wi-Fi technology. Each node or computer in the LAN has its own computing power but it can also access other devices on the LAN subject to the permissions it has been allowed. These could include data, processing power, and the ability to communicate or chat with other users in the network.


MAPI is an acronym for Messaging Application Programming Interface implemented in Microsoft Windows. MAPI allows client programs to become (electronic mail) messaging-enabled, -aware, or -based by calling MAPI subsystem routines that interface with certain messaging systems and message stores. MAPI refers both to the application programming interface as well as the proprietary protocol which Microsoft Outlook uses to communicate with Microsoft Exchange.


Microsoft Data Access Components (commonly abbreviated MDAC) is a group of Microsoft technologies that interact together as a framework that allows programmers a uniform and comprehensive way of developing applications for accessing almost any data store. It is made up of various components: ActiveX Data Objects (ADO), OLE DB, and Open Database Connectivity (ODBC). There have been several deprecated components as well, such as the Microsoft Jet Database Engine, MSDASQL, and Remote Data Services (RDS). Some components have also become obsolete, such as the former Data Access Objects API and Remote Data Objects.


A modem (from modulate and demodulate) is a device that modulates an analog carrier signal to encode digital information, and also demodulates such a carrier signal to decode the transmitted information. The goal is to produce a signal that can be transmitted easily and decoded to reproduce the original digital data. Modems can be used over any means of transmitting analog signals, from driven diodes to radio. Experiments have even been performed in the use of modems over the medium of two cans connected by a string.


Notepad is a simple text editor included with all versions of Microsoft Windows since version 1.0 in 1985.


Open Database Connectivity (ODBC) provides a standard software API method for using database management systems (DBMS). The designers of ODBC aimed to make it independent of programming languages, database systems, and operating systems.


Portable Document Format (PDF) is an open file format created by Adobe Systems in 1993 and is now being prepared for submission as an ISO standard. It is for representing two-dimensional documents in a device independent and resolution independent fixed-layout document format. Each PDF file encapsulates a complete description of a 2D document (and, with the advent of Acrobat 3D, embedded 3D documents) that includes the text, fonts, images, and 2D vector graphics that compose the document. PDF files do not encode information that is specific to the application software, hardware, or operating system used to create or view the document. This feature ensures that a valid PDF will render exactly the same regardless of its origin or destination (but depending on font availability when fonts are not encapsulated in the file).


PNG (Portable Network Graphics) is a bitmapped image format that employs lossless data compression. PNG was created to improve and replace the GIF format, as an image-file format not requiring a patent license.


Local e-mail clients use the Post Office Protocol version 3 (POP3), an application-layer Internet standard protocol, to retrieve e-mail from a remote server over a TCP/IP connection. Nearly all subscribers to individual Internet service provider e-mail accounts access their e-mail with client software that uses POP3.

Printer Driver

A printer driver is a piece of software that converts the data to be printed to the form specific to a printer. The purpose of printer drivers is to allow applications to do printing without being aware of the technical details of each printer model.

Proxy Server

A proxy server is a computer that offers a computer network service to allow clients to make indirect network connections to other network services. A client connects to the proxy server, then requests a connection, file, or other resource available on a different server. The proxy provides the resource either by connecting to the specified server or by serving it from a cache. In some cases, the proxy may alter the client's request or the server's response for various purposes.

Display Resolution

The display resolution of a digital television or computer display typically refers to the number of distinct pixels in each dimension that can be displayed. It can be an ambiguous term especially as the displayed resolution is controlled by different factors in picture-tube (CRT) and flat panel or projection displays using fixed picture-element (pixel) arrays.

Registry Editor

The registry can be edited manually in Microsoft Windows by running regedit.exe or regedt32.exe in the Windows directory. However, careless registry editing can cause irreversible damage. Thus, performing back-up for registry is needed. Many optimization and "hacking" tools are available to modify this portion of the Windows operating system. It is preferable to use one of the many registry tools available, unless you have a knowledge of registry workings or wish to learn more about the registry, in which case it is recommended that you back up your hard drive before changing the registry.


Computer shortcuts are small files containing only the location of another file.


Short Message Service (SMS) is a service available on most digital mobile phones,other mobile devices (e.g. a Pocket PC, or occasionally even desktop computers) and some fixed phones, that permits the sending of short messages between mobile phones, other handheld devices and even landline telephones. The terms text messaging, text messages, more colloquially SMSes, texts, or even txtsand its variants are more commonly used in North America, the United Kingdom, Spain and the Philippines, while most other countries (Russia, for example) prefer the term SMS.


Simple Mail Transfer Protocol (SMTP) is the de facto standard for e-mail transmissions across the Internet. The protocol used today is also known as ESMTP.


SOCKS is an Internet protocol that allows client-server applications to transparently use the services of a network firewall. SOCKS is an abbreviation for “SOCKetS.”


Spamming is the abuse of electronic messaging systems to send unsolicited bulk messages, which are almost universally undesired. While the most widely recognized form of spam is email spam, the term is applied to similar abuses in other media: instant messaging spam, Usenet newsgroup spam, Web search engine spam, spam in blogs, mobile phone messaging spam and junk fax transmissions.


SQL (commonly expanded to Structured Query Language) is the most popular computer language used to create, retrieve, update and delete data from relational database management systems. The language has evolved beyond its original purpose, and now supports object-relational database management systems. SQL has been standardized by both ANSI and ISO.

Start Menu

The Start Menu and Start Button are user interface elements in the Microsoft Windows product line, which serve as the central launching point for applications.

System Tray

The system tray, or “notification area”, is the portion of the taskbar that displays icons for system and program features that have no presence on the desktop as well as the time and the volume icon. It contains mainly icons that show status information. By default, this is located in the bottom-right of the primary monitor, or at the bottom of the taskbar if docked vertically. The clock appears here, and applications can put icons in the notification area to indicate the status of an operation or to notify the user about an event.


The taskbar is a term for the application desktop bar which is used to launch and monitor applications in Windows operating systems.

TCP Port

In the TCP and UDP protocols used in computer networking, a port is a special number present in the header of a data packet. Ports are typically used to map data to a particular process running on a computer. As an example, a server used for sending and receiving email may provide both an SMTP and a POP3 service; these will be handled by different server processes, and the port number will be used to determine which data is associated with which process. This may be considered loosely analogous to simulating the effect of a single server with multiple physical connections. Note that not all transport layers use network ports; for example, although UDP and TCP use ports, ICMP does not.

Ten-Digit Dialing

In the United States and Canada, 10-digit dialing is a popular term used to refer to the practice of including the area code of a phone number when dialing. It is also sometimes known as national format.


Tagged Image File Format (abbreviated TIFF) is a file format for mainly storing images, including photographs and line art. Originally created by the company Aldus, jointly with Microsoft, for use with PostScript printing, TIFF is a popular format for high color depth images, along with JPEG and PNG.


Unicode is an industry standard designed to allow text and symbols from all of the writing systems of the world to be consistently represented and manipulated by computers. Developed in tandem with the Universal Character Set standard and published in book form as The Unicode Standard, Unicode consists of a character repertoire, an encoding methodology and set of standard character encodings, a set of code charts for visual reference, an enumeration of character properties such as upper and lower case, a set of reference data computer files, and rules for normalization, decomposition, collation and rendering.

Universal Naming Convention

The Universal Naming Convention, or UNC, specifies a common syntax to describe the location of a network resource, such as a shared file, directory, or printer. The UNC syntax for Windows systems is as follows:


where computername is the hostname, sharedfolder is a shared directory with a name chosen by the host providing the share, and resource is a shared directory, file, or printer. The hostname may also be identified by a fully-qualified domain name or by IP address. The sharedfolder may exist anywhere on the remote host system, and is not restricted to the filesystem root directory.


The Universal Product Code (UPC) is one of a wide variety of bar code languages called symbologies. The UPC is the barcode widely used in the United States and Canada for items in stores.


Uniform Resource Locator (URL) is a technical, Web-related term used in two distinct meanings: In popular usage, it is a widespread synonym for Uniform Resource Identifier (URI) — many popular and technical texts will use the term "URL" when referring to URI; Strictly, the idea of a uniform syntax for global identifiers of network-retrievable documents was the core idea of the World Wide Web. In the early times, these identifiers were variously called "document names", "Web addresses" and "Uniform Resource Locators


A Computer Virus is a computer program which distributes copies of itself, even without permission or knowledge of the user. A computer virus is often simply called a virus if it is clear from the context that it does not refer to a biological virus. The term is commonly used to refer to a range of malware, but a true virus does not need to be harmful. To distribute itself, a virus needs to be executed or interpreted. Viruses often hide themselves inside other programs to be executed.


A virtual private network (VPN) is a private communications network often used within a company, or by several companies or organizations, to communicate confidentially over a public network. VPN traffic can be carried over a public networking infrastructure (e.g. the Internet) on top of standard protocols, or over a service provider's private network with a defined Service Level Agreement (SLA) between the VPN customer and the VPN service provider.

Wide Area Network

Wide Area Network (WAN) is a computer network that covers a broad area (i.e., any network whose communications links cross metropolitan, regional, or national boundaries). Or, less formally, a network that uses routers and public communications links. Contrast with personal area networks (PANs), local area networks (LANs), campus area networks (CANs), or metropolitan area networks (MANs) which are usually limited to a room, building, campus or specific metropolitan area (e.g., a city) respectively. The largest and most well-known example of a WAN is the Internet.

Windows Registry

The Windows registry is a database which stores settings and options for the operating system for Microsoft Windows 32-bit versions, 64-bit versions and Windows Mobile. It contains information and settings for all the hardware, operating system software, most non-operating system software, users, and preferences of the PC and so on. Whenever a user makes changes to “Control Panel” settings, or file associations, system policies, or installed software, the changes are reflected and stored in the registry.


The Extensible Markup Language (XML) is a W3C-recommended general-purpose markup language that supports a wide variety of applications. XML languages or 'dialects' may be designed by anyone and may be processed by conforming software. XML is also designed to be reasonably human-legible, and to this end, terseness was not considered essential in its structure. XML is a simplified subset of Standard Generalized Markup Language (SGML). Its primary purpose is to facilitate the sharing of data across different information systems, particularly systems connected via the Internet.


The ZIP file format is a popular data compression and archival format. A ZIP file contains one or more files that have been compressed, to reduce their file size, or stored as-is.