Glossary (Internet Terms/Definitions)

Active Channel
An Active Channel is a frequently updated information residing on a Web server. Users can subscribe to the channel if they have a CDF (Channel Definition Language) capable browser.

ActiveX
ActiveX is a brand name referring to a set of Microsoft's technologies and services based on COM (Component Object Model). On the Internet, ActiveX can be used with IE versions 3 and above and with Netscape Navigator though plug-ins.  Once downloaded, ActiveX controls have a large degree of freedom, presenting a security risk.  ActiveX controls have to be digitally signed by their creator.  Major competitor to ActiveX controls are JavaBeans. Some hosts support ActiveX server components for ASP.

Address
Unique identifier of a web page. URL (Uniformed Resource Locator) is more frequently used for this purpose.

ADN
(Advanced Digital Network). A 56kbps dedicated communication line.

ADO
ActiveX Data Objects. Different data sources can be accessed in the same way within a single data model. The data can be located in various locations, like spreadsheets, databases or ordinary files.

AIFF
Audio Interchange File Format. High quality audio file format introduced by Apple.

Anonymous FTP (Anon FTP)
A method for downloading and uploading files using FTP protocol without having a username or a password.  In place of a username, word "anonymous" is used, and in place of a password, email address is usually used.  If a hosting plan offers this service, your users will be able to download or upload files with FTP without having their own account.

Apache
Apache is an open-source (source code is freely available and can be shared) HTTP Web server software. It is usually run on Unix operating system versions like Linux or BSD, but it can also be run on Windows.

Applet
Most often refers to a small Java program designed to run in a Web browser. Java applets run in a sandbox, so they can't perform unauthorized functions like file reading or opening Net connections to other computer from your computer.

ASCII
(American Standard Code for Information Interchange). A standard for coding text files. Every character has an associated number and any text can be represented by a sequence of numbers.

ASP
Active Server Pages.  ASP is Microsoft's server-side scripting technology. An Active Server Page has an .asp extension and it mixes HTML and scripting code that can be written in VBScript or JScript. ASP is distributed with Microsoft's IIS web server, so most host using IIS will also offer ASP for dynamic web programming. ASP.NET is the next version of ASP.  Other popular server-side scripting languages are Perl, PHP, ColdFusion, TCL, Python, and JSP.

Asynchronous Transfer Mode (ATM)
A set of network protocols designed for multimedia transmission. Data is partitioned into cells (53 bytes each) and passed along a virtual circuit. ATM allows for building very high speed networks.

AU
Audio file format for Unix systems.

Authentication
Authentication is used to confirm the identity of the other party involved in the data transmission.

 
AVI
Audio/Video Interleave. Audio file format used by Microsoft Widows.
 

B Channel
Bearer Channel. It is a 64 Kbps communication channel in ISDN.

Backbone
Main high-speed network connection composing the Internet. Backbones are operated by major telecommunications companies.

Bandwidth
Bandwidth is the amount of data that can be transferred over the network in a fixed amount of time.  On the Net, it is usually expressed in bits per second (bps) or in higher units like Mbps (millions of bits per second). 28.8 modem can deliver 28,800 bps, a T1 line is about 1.5 Mbps.

Baud Rate
The rate at which bits are transmitted over a communication link. Baud is the number of transitions (that are used to encode bits) that take place in one second.

Binary
Data represented in binary format uses only two digits - 0 and 1.

Binary mode
FTP client mode used to transfer binary files (multimedia files, executables and other data files). Not suitable for transferring normal text files.

Bit
(Binary DigIT) the smallest unit of information, comprising of either a 1 or 0.

Bit rate
The speed at which bits are transmitted over a communication link. Expressed in bits per second (bps).

Body
The part of an email message that contains the actual text of the message.

Bot
An automated piece of software that can be used in chat rooms or to crawl the web.

Bridge
A network device used to connect two LANs using different cabling.

Broadcast
Sending a packet to all machines on the network.

Browser sniffing
The process in which the web site tries to determine what kind of web browser the user is using. This is done to suit the website to the particular capabilities of the browser.
 

C/C++
Popular programming languages (C++ includes objects) that can be used to create server programs that run after compilation.  C and C++ were not designed specifically for web programming, but they can still be useful, especially because mature compilers producing very fast code and large code libraries already exist.

Cascading Style Sheets (CSS)
A style-sheet determines how the HTML document is displayed by the browser. The current version of CSS is version 2 (CSS2).

Certificate
Digital ID used for SSL transactions.  It includes owner's public key, the name of the owner, the issuer, hostname, and the expiration date.

Certificate Authority
A company trusted by a browser maker that issues digital certificates that are supposed to guarantee that the company is what it claims to be for use in encrypted digital transactions though SSL.

CGI
Common Gateway Interface.  A standard for interfacing web servers with an executable application.  A CGI program can be written in any language like Perl or C/C++ and it is often stored in a special directory like /cgi-bin. CGI is often used to process data from HTML forms.

cgi-bin
A directory on the server where the executable CGI scripts reside.

Channel Definition Format (CDF)
A way of defining the server-push channels for accessing frequently changing web content.

Client
A computer program that requests a service from the server program, usually over the network.

 
Client/Server
A network architecture where a system is divided into two parts: the client and the server.

Clustering
Connecting many computers and making them appear as one machine. This is done to increase reliability and performance.

Co-location
Putting a web server in a dedicated facility that provides high-speed Internet connection, security, environment, backup power, and technical support. Unlike the dedicated server, the client controls both hardware and software.

Cobalt RaQ
Server appliance made by Cobalt specifically for hosting companies. Newest RaQs are Linux-based and provide an easy-to-use interface. RaQs have no features that can't be had in a regular Linux box but they offer pre-installed programs and Cobalt's support.

ColdFusion
ColdFusion is an easy to use server-side scripting language.  Other popular server-side scripting languages are ASP. Perl, PHP, TCL, Python, and JSP.

Command-line interface
The opposite of the GUI (Graphical User Interface). A way of interacting with a computer system using the keyboard and a text-only display. Usually more powerful, but less user-friendly that a GUI.

Control Panel
Control panel included in web hosting packages is an online web-based application that allows you to easily manage different aspects of your account. Most control panels will let you upload files, add email accounts, change contact information, set up shopping carts or databases, view usage statistics, etc.

Cookie
A Cookie is a piece of data that is saved in the user's browser by the web server. It is used to customize user's browsing experience.

Crawler
Also known as spider, an automated software that retrieves web pages and follows the hyperlinks contained in them. Used to generate indexes used by search engines.

D Channel
The ISDN signaling channel. Runs at 16 or 64 Kbps.

Data transfer
In Web hosting, the total size of files transferred by an account in a month. Sites with a lots of graphics, downloads, or streaming audio or video and a lot of visitors will require plans with more available transfer.

Database
Data in a structured format stored on a web server.  Most popular type is a relational database. The most common query (information retrieval) language for relational databases is SQL.  Linux-based hosts most commonly include MySQL database and Windows NT-based hosts usually include Access or MS SQL databases.

Dedicated Server
Similar to co-location, except that you lease or rent hardware from a Web host. The main advantage over co-location is easier upgrade and usually better support. Getting a dedicated server or co-locating is necessary for sites that outgrow shared servers because they use a lot of bandwidth and resources or they require total control over software environment.

DES
Data Encryption Standard - an U.S. government approved cipher. It is easy to break in its simplest form, but used multiple times with key of at least 128 bits provides good security.

DHCP
(Dynamic Host Configuration Protocol). An automated way of obtaining an IP address in the Local Area Network.

DNS
Domain Name System.  Internet service that maps Internet domains into corresponding IP addresses. DNS database is distributed and replicated among many DNS servers, so when you change your domain's IP address, the changes take a while to propagate.

Domain name
A domain name is an easy-to-remember address that can be translated by DNS into server's IP address.

E-Business/eCommerce
Using web and Internet technologies in conducting the business activities. Also expanding end enhancing traditional business practices by means of the Internet.

Encryption
Encryption means encoding data using a cryptographic cipher. Encrypted data can be read (decrypted) only by an authorized entity.

Filename extension
Last three or four letters of a file name that appear after the dot. Used to designate the type of file and the format used.

Filtering
Screening network packets for certain properties, such as the source or destination address, protocol used or even a pattern in the data. It is used in firewalls in order to decide if the traffic is to be forwarded or rejected. Provides the basis for network security.

Firewalls
Firewall refers to either software-only or separate software and hardware combination that serves to protect an internal network or a computer from attacks and unauthorized access by sitting between the Internet and the internal network. For more on firewalls, click here

FPU
Floating Point Unit. A part of the computer responsible for high precision mathematical operations.

FrontPage Extensions
Microsoft's server-side applications that lets users of FrontPage Web site creation tool to incorporate "web-bots" that perform pre-packaged function like full-text Web site searching or adding a hit counter. FrontPage extensions are also available for Unix-based operating systems but some hosts refuse to use them because of potential security holes.

FTP
"File Transfer Protocol" is the Internet protocol defining how to download and upload files between a client and an FTP server.

FTPmail
Using email messages to access the FTP sites. Requires a special software installed on the server.

Gateway
A network device used to translate between two different protocols. Used to interconnect two networks that use incompatible protocols.

GIF
(Graphics Interchange Format) A graphic file format invented by Compuserve. One of the most widely used formats for internet and web. Uses a lossless compression method, thus ensuring that the quality of the image is not lowered.

Gigabyte (Gb)
1024 Megabytes.

Graphical User Interface (GUI)
A way of interacting with the computer that relies on graphical symbols. Most often requires a mouse. It is less powerful then the command-line interface, but is more user friendly and is easier to learn for users without technical background.

Hit
In the WWW world "hit" is used to describe a single request made by a web browser. The data transmitted by the web server in response to the request is a text file or a binary file (images, audio, video, executables and other data).

Home Page
Main web page owned by a company, organization or an individual. This is the page that is initially displayed when user makes a request for a particular domain name.

Host
A networked computer dedicated to providing a certain kind of service. Usually refers to a computer that stores the website files and has a web server running on it.

HTML
(Hypertext Markup Language). It is the language in which web pages are written. It allows the images to be combined with text and offers wide range of formatting capabilities. One of the most important features of HTML is hypertext, that allows web pages to be liked one to each other.

HTTP
Hyper Text Transfer Protocol.  The main protocol used to transfer and receive data over the World Wide Web. The latest version of HTTP is 1.1. Basic HTTP transaction involves a WWW browser connecting to a server, browser sending a request to the server specifying its capabilities and which document is requested, server responding with the required data, and closing of the connection.

Hyperlink
A part of the web page that links to another web page. By clicking on a hyperlink user redirects the browser to another page. The word hyperlink is sometimes shortened to just "link".

Hypertext
A text on the web page that is linked to another webpage. Browsers usually display hypertext as underlined and in blue color.

IIS
Microsoft Internet Information Server. Microsoft's Web server that comes built-in with Windows NT Server 4 and Windows 2000 server.

Image Map
An image displayed on the webpage that has different areas that are hyperlinks. By clicking on different parts of the image browser can be redirected to another webpage, or can display modified version of the current one.

IMAP
Internet Message Access Protocol. A method allowing a client email program to access remote messages stored on a mail server. The protocol includes operations for creating, deleting, and renaming mailboxes, checking for new messages, message parsing, searching, and setting and clearing flags. IMAP was originally developed in 1986 at Stanford.

Internet backbone
An extremely fast network that connects major cities. Most often it utilizes T3 circuits and provides the bandwidth of 45Mbps.

Internet Group Management Protocol (IGMP)
A network control protocol running on top of the IP protocol. It is used by Internet hosts to maintain information related to multicast. All machines that want to use the multicast have to have the IGMP implemented.

InterNIC
The organization that handles domain name registrations.

Intranet
A part of an organization's network that is private. Only authorized individuals have access to the intranet. Besides that an intranet is very similar to the Internet in a sense that it offers the same services and uses the same protocols.

IP
(Internet Protocol) is the main protocol used on the Internet.

IP Address
Internet Protocol Address.  A unique number identifying all devices connected to the Internet.  This number is usually shown in groups of numbers from 0 to 255, separated by periods, for example  125.255.255.123.

IP packet
IP packet is the basic data chunk that can be sent over the Internet. All the data is partitioned into IP packets on the sending computer and reassembled on the receiving computer.

Java
Java is a platform-independent, crash-protected, object-oriented language that can be used to write applets that run in a browser, servlets that run server-side, or independent programs.

Java class files
The file or set of files that contain the code for a Java applet.

Java Servlet
Servlets are programs written in Java that run on a Web server and can produce dynamic pages.

Java Virtual Machine (JVM, Java Runtime Environment)
A set of programs that allow for Java applets to be run on a particular computer system.

JavaScript
Simple, client-side programming language created by Sun and Netscape. JavaScript can be embedded in HTML pages to create interactive effects and do tasks like validate form data. JavaScript is a separate language from Java and all popular modern browsers support JavaScript. A few hosts support server-side JavaScript.

JDBC
Java Database Connectivity - a mechanism allowing Java applets to access different databases.

JPEG
(Joint Photographic Experts Group) A image compression format designed for the Internet. Uses lossy compression, meaning that the quality of the image can be lowered.

JScript
A Limited, object-based, interpreted scripting language comparable to VBScript.

JSP
"Java Server Pages" is an extension of Java Servlet technology for combining Java server-side programs and HTML.  JSP pages have an extension .jsp.

Kbps
Kilobits per second. 1Kbps = 1024bps.

Kilobyte (Kb)
1024 bytes.

Link
Another name for a connection. Sometimes refers to a physical line.

Linux
A free UNIX-like operating system very often used by hosting companies as their operating systems.

Login
An alias for an individual that is used for identification and authentication when accessing a computer system. Usually it is a sequence of characters and digits.

Lossy
A lossy compression allows for the quality of the compressed data to be diminished after decompression. It is suitable for audio, video and image compression.

Mailserver
The Internet host (together with the appropriate software) that is used to send, receive and forward email messages.

Mainframe Computer
A powerful computer used for computing-intensive tasks.

MBps
MegaBytes (MB) per second, 1 MB = 1,048,576 bytes

Mbps
Megabits (Mb) per second, 1Mb = 1,048,576 bits

Megabyte (MB)
1MB = 1024 KiloBytes = 1,048,576 bytes

MHz
MegaHertz = 1.000.000 Hertz

Microsoft SQL Server
Microsoft's high-end SQL database running on Windows systems.

MIME
(Multipurpose Internet Mail Extensions) a method of including binary data and other multimedia content within email messages.

Mirror site
An FTP site that stores the exact content of some other site. Mirroring is done in order to minimize the load on a particular server and also to increase reliability.

.mov
File name extension for files with video sequences. QuickTime player is required in order to play this type of file extension.

MP3
An extremely popular lossy audio compression format. Widely used over the Internet.

MPEG
(Motion Picture Experts Group) video compression format for movies or animations.

Multicast
A message that is sent to a specific group of hosts.

MySQL
Most popular open-source relational database.  Many Unix-based plans allow MySQL databases.

Nameservers
Sometimes referred to as a "host" or a "DNS information server" it is a computer (server) that translates DNS names into numerical IP addresses. In order to do this it has both the software and the data (zone files) needed to resolve domain names to Internet Protocol (IP) numbers. Important- each domain name must be programmed into a minimum of two nameservers hosted on separate networks in order to work "resolve" properly..

Network
A group of electronic devices connected together that are able to communicate with each other.

NIC
Network Interface Card - a part of the computer hardware responsible for connecting a particular machine to the local area network.

NNTP
(Network News Transfer Protocol) An Internet protocol that describes how the newsgroups messages are distributed, stored, posted and retrieved.

ODBC
(Open Database Connectivity) A standard allowing applications to access different databases in an uniform way.

Offline
The state of the computer/server when it is not connected to the network.

Online
The state of a computer when it is connected to the network and communicate with other machines.

Operating system
The server or computer's base software interface "environment" for application programs to run and provide a user interface (runs a set of programs which manage the hardware resources of a computer).

Page
Name for a basic web document. Websites usually consist of many (web) pages.

PAP
(Password Authentication Protocol). PAP is the authentication protocol used over PPP connections.

Peer-to-Peer network
A peer-to-peer network is a collection of computers that can communicate and share information, but that don't have any kind of hierarchical structure. This is the opposite of the client/server model.

Perl
An open source CGI scripting programming language which is one of the most popular web programming languages (uses text-manipulation facilities).

PHP
Similar to C and Java, PHP is an free, open-source server-side scripting language which can be embedded in HTML code.

Plug-in
An add-on piece of software that can extend the features of an existing application. For example Netscape browser plug-ins allow displaying of new types of web content, that the browser can't display on its own.

POP
Post Office Protocol.  Popular but inflexible email retrieval standard. All messages are downloaded at the name time and can only be manipulated on a client machine.  Current version is POP3.

Port
A socket on the computer or other network device used to connect it to the network.

PPP
(Point to Point Protocol) A network protocol widely used to connect computers to the Internet. Most often used on a telephone line.

Protocol
A set of rules by following which two parties can communicate. The TCP/IP protocol suite is the basis of today's Internet.

Python
Interpreted programming language, sometimes offered by hosts for server-side scripting.

RAID
Redundant Array of Independent (or Inexpensive) Disks.  Type of disk, often used on servers, where several physical disks are combined into an array for better speed and fault tolerance.

Raw Logs
Raw access data updated in real-time that can be downloaded and used by any statistics program. Typically shows a "visitors" IP address, date and time they accessed the site, which documents were requested, HTTP status code, bytes transferred, referrer...

S/MIME
Secure Multipurpose Internet Mail Extensions - a way of making email messages more secure. S/MIME uses digital certificates to attest the message origin and encryption to ensure that message could not be read while in transit.

Scripting Language
A programming language in which programs are the series of commands that are interpreted and then executed one by one. Doesn't require the compilation phase, for the price of lower performance.

Search engine
An Internet service that stores a vast number of web pages and allows for fast searching among them. Also, a piece of software that implements a website search functionality.

Search form
An online form in which a query to the web page's database is specified.

Self-extracting Archive
An archived file that is also an executable program. The original archived file is decompressed when that program is run.

Serial Line Internet Protocol (SLIP)
Another network protocol used to connect computers to the networks. Similar to PPP.

Server
A networked computer that handles client requests for Web pages.

Session
All the data exchange between two parties, starting when the connection is established and ending when connection terminates.

Setup fee
Initial fee charged by a host to set up your hosting account.

Shopping Cart
Software that allows users to select products from a Web catalog, modify their choices, calculate prices, review their choices, and order them. Many hosts with e-commerce plans offer installed shopping carts, but you can always get a shopping cart of your choice instead.

SHTTP
Secure HTTP. A version of HTTP protocol that uses encryption to assure that the traffic between the server and the browser cannot be eavesdropped on. Should be considered mandatory for all e-commerce applications.

Signed applet
An applet that has a digital signature to confirm that it originates from the legitimate server.

SMTP
Simple Mail Transfer Protocol.  Very popular protocol used to transfer email messages across the Internet mail servers.

SNMP
(Simple Network Management Protocol). A most widespread protocol used for network management.

Spam
Unsolicited email sent in mass quantities to multiple recipients, most often for marketing purposes. Highly annoying and constituting one of the most serious netiquette violations.

Spider
An automated software that retrieves web pages and follows the hyperlinks contained in them. Used to generate indexes used by search engines.

SPX
(Sequenced Packet Exchange). A proprietary Novell network protocol used in conjunction with IPX.

SQL
"Structured Query Language" is a limited programming language used for updating and performing queries on relational databases. All databases share a common subset of SQL.  Most popular SQL databases available with hosting plans are MySQL and MS SQL.

SSI
"Server-Side Includes" instruct the server to include some dynamic information in a Web page before it is sent to a client. This dynamic information could be current date, an opinion poll, etc.  Many hosts require that SSI pages have .shtml extension to reduce the load on servers by not having to parse non-SSI pages.

SSL
"Secure Sockets Layer" protocol was developed by Netscape to provide encryption for commercial transactions data that should be protected while traveling over the Internet, like credit card numbers.  SSL uses https protocol. Before using SSL in commerce, you'll also need to get is a certificate from a Certificate Authority.

Static (or dedicated) IP
If a host offers a static IP, it means that your site will be assigned a unique and unchanging IP address.

Streaming
Playing multimedia files (audio and video) without requiring a full download. Audio and video are compressed but they still may require more bandwidth.

Sub-domain
Sub-domains are a way to divide a web site into sections with short, easy to remember names. Some larger websites might point their sub-domains to another server to reduce bandwidth load on the main site.

Switch
A switch is a network device that forwards packets. Switches are more intelligent than hubs in a sense that they forward packets only to the necessary ports and not to all the ports.

TCP
(Transmission Control Protocol) is the most important of the network protocols used in the Internet.

TCP/IP
(Transmission Control Protocol/Internet Protocol). This protocol suite is the de facto standard for the today's Internet. TCP is a higher level protocol that runs on top of the IP protocol.

Terabyte (TB)
1024 gigabytes

Traceroute
A computer program that lists network hosts visited by a packed on the way to its destination. Very useful for network debugging.

Traffic
Data packets being transmitted over a network.

Unicode
A 16 bit ISO 10646 character set. It can accommodate way more characters that ASCII, thus allowing for easier internationalization.

Unix
A family of multi-user operating systems, first developed in the 1970s. It is a basis for the Linux operating system.

UPS
Uninterruptible Power Supply. UPS keeps the server running on a battery for several minutes after a power outage, allowing for a clean shutdown without loss of data. UPS can also shield the server from line voltage spikes and drops.

VBScript
Is a Microsoft Visual Basic Scripting Edition language (subset of MS Visual Basic language) for creating scripts that can be embedded in HTML pages or for creating ActiveX Controls. Meant as an alternative to JavaScript and is comparable to JScript.

Viewer
An stand-alone application used to display files of different formats.

VPN
(Virtual Private Network). A virtual private network is a method of accessing the private network in a secure way over public communication lines and networks.

WAV
An audio file format. Very accurate, but offers no compression, thus resulting in very large files.

Webmaster
A person responsible for the maintenance of a particular website.

whois
An Internet service allowing to obtain the information about the domain name owner and/or nameserver information.

Wide Area Network (WAN)
A set of computers that are to far apart to constitute a LAN. In fact, WANs are very often composed of a number of Local Area Networks interconnected together.

WWW
World Wide Web (or Web) is the most popular Internet service. It allows access to the information and services from the web servers. A web browser is needed to use the Web.

XML
"Extensible Markup Language" is a meta-language, abbreviated version of SGML, used to specify other document types used on the Web. Created to replace HTML.

XML processor
A program that can XML documents and access their content.

.ZIP
File name extension for compressed files.