Important Terms for Online Transactions

Authenticate, encryption, server, spider. What are they and how do they affect your online transactions? Get definitions for these important terms and more.

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ASCII (pron. “as-key”): American Standard Code for Information Interchange. A standard way of representing ordinary text as a stream of binary numbers with a code set of 128 characters. The first 32 characters are control codes, and the remaining 96 are letters (both uppercase and lowercase), numbers, punctuation marks, and special characters.

Authenticate: To verify the identity of an Internet user or computer. Example: Before accepting an online order, some merchants will use advanced security systems to authenticate the customer’s identity.


Bandwidth: The maximum speed at which data can be transmitted between computers in a network.

Banner: An advertising component of a Web page that is usually an inch or less tall and spans the width of the Web page. The banner contains a link to the advertiser's own Web site.

Baud rate: The rate at which a modem can transmit data. This is measured in bits per second (bps). Named after the French engineer Jean Maurice Emile Baudot.

Bit: The smallest unit of information understood by a computer. A bit can take a value of 0 or 1. A byte is made up of 8 bits, which is large enough to contain a single character. Example: When represented in bits, the character 2 would be equivalent to “00000010.”

Bookmark: A bookmark is the URL for a particular Web page, as stored by the user. The user can select the bookmark in the future to automatically retrieve that Web page.

Browser (also Web browser): An application program that interprets HTML and presents the final Web page; used to surf the World Wide Web. Examples include Microsoft ® Internet Explorer and Netscape ® Navigator.

Byte: A group of eight binary digits processed as a unit by a computer and used especially to represent an alphanumeric character. Also, a unit of computer information equivalent to the result of a choice between two alternatives (as “yes” or “no,” “on” or “off”).


Cache (pron. “cash”): A small, but very fast type of memory used to store frequently used data. It tries to “guess” what data is going to be needed next by the processor, based on historical data.

Cookie: Small text files placed on a user's computer by a Web server. Each cookie contains unique identifying characteristics, usually in the form of a long string of seemingly random characters. A cookie can later be read by the same server and matched against the server's own database in order to learn which pages on that server have already been viewed.

Cryptography: The process of scrambling and unscrambling information so that only the intended parties can read it. Example: When a customer makes a purchase online, cryptography can prevent everyone but the intended merchant from reading the user's Visa account number and card expiration date.

Cyberspace: The online world of computer networks. The term was coined by science fiction writer William Gibson in his 1984 novel, Neuromancer.


DES: Data Encryption Standard. A commonly-used standard method for encrypting and decrypting data; developed by the U.S. National Institute of Standards & Technology. Encryption is critical, with valuable and sensitive information being sent from one computer to another via a network that, technically, can be accessed by anybody. DES provides a degree of security should the information fall into the wrong hands.

Dial-up connection:A temporary connection between two computers via a telephone line, normally using a modem.

DNS:Domain Name System. How the Internet links together the thousands of networks that comprise the Web. DNS is used whenever an email is sent or a Web page is accessed. Each computer on the Internet has one or more domain names. Example: In “,” the .co indicates a commercial organization and the .uk indicates that the computer is physically located in the United Kingdom.

Standard conventions used in domain names include:

ac - Educational institution

co - Commercial organization

com - Commercial organization

edu - Educational institution

gov - Non-military government organizations

int - International organizations

mil - Military government organizations

net - Networks

org - Non-profit organization

These codes are also included in certain URLs, such as “” The DNSs convert the domain names to a unique number known as an IP (Internet Protocol) address. You will often see the IP address displayed next to your Web browser when you are connecting to a particular computer.

Domain name: A unique name that represents each computer on the Internet. (Note that some machines do have more than one domain name.) The DNS converts the domain name request into an IP address.

Download: To copy files from one computer or server to another via a network or modem.


e-Commerce: Business that takes place between companies using electronic services such as the Internet, Electronic Data Interchange, or Electronic File Transfer. Two companies—the supplier and the customer—can transmit inquiries, orders, invoices, or payments directly through their computer systems.

Email: Electronic Mail. A way of sending other people messages from your computer. Basically, email sends addressed messages over a network.

An email address consists of two halves —a user name and a domain name—joined by the @ sign ( Example, if you’re on AOL and your screen name is Bruno, your email address will be

Encryption: The process of converting data into “unreadable code” so that prying eyes cannot understand the content. Encryption is critical, as valuable and sensitive information is often sent from one computer to another via a network that, technically, can be accessed by anybody. It provides a degree of security should the information fall into the wrong hands.

Extranet: Very similar to an intranet, with the added feature that the information contained can be accessed externally by business partners.


FAQ: Frequently Asked Questions. A set of often-asked questions about a given topic at a Web site. A site owner posts a list of the queries and answers, and then the user can access this FAQ at any time.

File extension: The part of a file name that corresponds to that file's type. Computer files are labeled using a standard: a name, a point, and a file extension. Example: AUTOEXEC.BAT has a file extension of BAT, indicating it is a batch file.

Firewall: A combination of specialized hardware and software designed to keep unauthorized users from accessing information within a networked computer system.

FTP: File Transmission Protocol. A standard for moving files from one computer to another; predominantly used on the Internet. Example: The master copy of this Glossary section resides on Visa's computer. When a change is made to the section, Visa uses FTP to transfer the updated files to the computer of its Internet Service Provider.

FTP Site: A computer on the Internet that specifically stores files for users to FTP to their own computers. When the FTP site does not require the user to have a specific user ID and password, it is called an “anonymous FTP site.”


GIF: Graphics Interchange Format. The most common type of image file used on the Internet. These files are compressed, taking up a minimum amount of space, and can therefore be downloaded a lot quicker than other graphics files. GIFs are often used for backgrounds, banner ads, or buttons. They can be animated or transparent, but are limited to 256 colors. Interlaced versions are designed to allow the image to be gradually revealed as it is downloaded. The file extension “.gif” is used for GIF files.


Hacker: A person who deliberately logs on to other computers by somehow bypassing the security system. Some hackers do this to steal valuable information or to cause irreparable damage.

Hit: The retrieval a Web page when it is accessed by a user or a program. Every time you click through to a Web site, a hit is registered.

Homepage (also, Welcome page): The opening page of a Web site. It should contain site navigation and appropriate contact information.

Host: Any computer that can function as the beginning and end point of data transfers. An Internet host has a unique Internet address (IP address) and a unique domain or host name.

HTML: HyperText Markup Language. The text-based language used to construct Web pages, interpreted by Web browsers.

HTTP: HyperText Transfer Protocol. The protocol used by the World Wide Web that dictates how communications are formatted and transmitted, and how Web servers and browsers respond to various commands. When you select a link, you are sending a request for that file to the http protocol on the computer hosting the Web site. Example: Selecting a link to “” sends a request to the hosting computer at Visa. The file is then transmitted to your Web browser.

Hyperlink: A highlighted, underlined phrase or word on a Web page that can be selected to proceed to either another part of the page or to another Web page.

Hypertext: Text that contains links that can be selected with a mouse. When the user clicks the link, they are taken to another document or a different section of the current document.


Internet: A worldwide network of computer networks. Through the Internet, you can send a note, chat with people electronically, or search for information on almost any subject.

Intranet: An internal or company network that can be used by anyone who is directly connected to the company's computer network (e.g., sales reps, partners, vendors).

IP address: Internet Protocol Address. A unique number that is used to represent every single computer in a network. All the computers in cyberspace have a unique IP address. The format of an IP Address is four sets of numbers separated by dots (e.g.,


Java: A modern programming language. First used in 1995 to bring Web pages to life. Java programs, called “applets,” are small in size and can be downloaded from the Internet and executed as part of the Web page being displayed.

JPEG: Joint Photographic Experts Group. A type of image file used on the Internet. Like GIF files, JPEGs are compressed. Unlike GIFs, JPEG files cannot be interlaced or transparent. The file extension “.jpg” is used for JPEG files.


Kilobyte: A unit of measure for data storage. One kilobyte is equivalent to 1,024 bytes or 8,192 bits.


Link: A component of a hypertext document that, when selected with a mouse, takes the user to either another document or a different section of the current document. Example: This glossary has links for each of the letters of the alphabet.

ListServ: List Server. A program that facilitates a subscription-based list that distributes email to the members, usually on a specific subject matter.


Mailbox: The file or directory where your incoming email messages are stored by your Internet Service Provider.

Mailing list: A single email address that comprises several different email addresses. Example: An automated software allows you to send email to one address. Then your message (e.g., a newsletter) is copied and sent to all of the other mailing list subscribers. The list can contain an unlimited number of people.

Megabyte: A unit of measure for data storage. One megabyte is equivalent to 1,024 kilobytes (or 1,048,576 bytes or 8,388,608 bits).

Menu: A list of options that enables a user to perform specific tasks.

Modem: From Modulation and Demodulation. A device that converts information from analog to digital and vice versa. Digital information is represented in a series of 1's and 0's. Analog information, such as a sound wave, varies continuously. Example: Typically, when an email is sent, the modem converts the digital email message to analog.

MPEG: Moving Picture Experts Group. A standard used on the Internet for video and audio files. Compression techniques enable the files to be transmitted significantly more quickly than other audio and video files. Web browsers must be able to run MPEG files. The file extension “.mpg” is used for MPEG files.

Multimedia: The presentation of video, sound, graphics, text, and animation via software.


News group: One of the many facilities available on the Internet. Like most of the Internet, news groups are run voluntarily and cooperatively. A news group is centered on a discussion topic, like business ownership (e.g., Within these news groups, several discussions or threads take place on themes within the specific topic. If you see a particular news group of interest, you can “subscribe” to it, and then “post” your comment or query. Eventually it will be seen by anyone else who subscribes to the particular news group.

Some categories of news groups include:

rec - recreational activities

biz - business related groups

comp - computers including technical discussion & support

soc - social issues

sci - scientific discussions

alt - alternative groups


Opt-in: A term popular in news groups and email. You can opt-in to receive emails on a certain subject. Example: By establishing an opt-in on your Web site, you can send customers an email when you have a sale.


Page impression:Occurs every time a particular Web page is displayed by someone using the Internet. A page impression is similar to a hit, except that a hit is also registered when a spider, or similar program, accesses the Web page.

Peripheral: A device that attaches to a personal computer and is controlled by its processor. Examples include printers, modems, joysticks, and Zip drives.

Plug and play: The concept of adding new components, such as an external modem, to a personal computer without having to manually configure anything. In other words, the operating system does it all for you.

Portal: A Web site that serves as a gateway to other sites on the Internet.

Profile:Personal information about you that’s stored with a merchant. A profile usually consists of a user's address and shopping preferences, making it easier for merchants to tailor services to individual needs.

Push technology: An Internet technology that sends prearranged information to users before they actually request it. The user sets up a profile specifying the type of information that they require.


Query: A word or series of words entered to retrieve database records that match certain criteria. Generally refers to databases. Example:


Radio button: Interactive element included in a list when users need to make a mutually exclusive choice. Each option in the list has a round button by it, and when a user clicks inside the circle, it becomes selected (e.g., goes from white to black). If a second option is selected, the first one becomes de-selected, because only one item can be selected from the list.

RTF: Rich Text Format. A file format developed by Microsoft to enable documents to be transferred between application programs. Most word processors can process RTF files. RTF files have the file extension “.rtf.”


Scalable: Easily expanded to suit future requirements. Applies to hardware or software. Example: An application program may be set up to run for two concurrent users, but can be scaled up for more users should the company using it expand in the future. This is very important in purchasing decisions.

Server: A host computer that stores information (e.g., Web sites) and responds to requests for information (e.g., links to another Web page). Also used to refer to the software that makes the act of serving information possible. Example: Commerce servers use software to run the main functions of an e-commerce Web site, such as product display, online ordering, and inventory management.

Shareware: Free software. However, the author usually requests a small fee to pay for registration and/or documentation.

Shortcut: An icon set up to lead to either a file on the hard disk, network, software program, or the Internet. When the icon is selected either the file is executed, the program starts, or an application opens with a selected document. Most commonly used in Windows.

SOHO : Small Office/Home Office. Describes businesses that are either run from home or a small office. Software and hardware companies sometimes promote products as being suitable for the SOHO market.

Spam: Unsolicited (usually commercial) email sent to a large number of addresses. Also used as a verb: To send unsolicited email to numerous addresses.

Spider: A search engine program that obtains its information by starting at a specified Web page and visiting each page linked to it, and so on. This process continues as a spider “crawls” its way across the Web.

SSL: Secure Sockets Layer. A security standard used by many merchants to keep their Web sites secure and to protect the safety, privacy, and reliability of payment data traveling over the Internet. SSL encrypts the channel between browser and Web server so that only the intended parties can read certain data, such as payment or customer information.

Surf: Visiting different sites on the Internet.


Thread: A series of messages or postings all related to the same topic. Often refers to Internet bulletin boards, email lists, and news groups.

Toolbar: Sits across the top or down the side of a particular window. The toolbar allows the user to perform certain tasks, such as opening a file or submitting a print. It can usually be customized to highlight the tasks most regularly performed.


Upload: To copy files from your own computer to another via a network or a modem. This is the opposite of download.

URL: Uniform Resource Locator. The address at which a Web page lives. Pages are identified by URLs. Hypertext links allow users to jump from page to page without typing in a long URL each time.


Virus:A program that can damage your computer's files. It is often created intentionally to do just that.

Visits: Indicates how many times a Web page has been accessed by Internet users. Example: if a site has received over 200,000 visits, the home page has been displayed by different users all over the world more than 200,000 times.


Web browser (also, Browser): An application program that interprets HTML and presents the final Web page. A browser is used to surf the World Wide Web. Examples include Microsoft® Internet Explorer and Netscape® Navigator.

Web page: An HTML document containing information that can be viewed from the Internet.

Web site: A group of Web pages that collectively represents a company, individual, or specific subject on the World Wide Web.

Welcome page (also, Homepage): The opening page of a Web site. It should contain site navigation and appropriate contact information.

WWW: World Wide Web. A browsable, interlinked collection of pages on the Internet.

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