Don’t see a definition below that you would like to suggest for the web hosting glossary? Please contact us
A loosely defined set of technologies developed by Microsoft. ActiveX is an outgrowth of two other Microsoft technologies called OLE (Object Linking and Embedding) and COM (Component Object Model). As a moniker, ActiveX can be very confusing because it applies to a whole set of COM-based technologies. Most people, however, think only of ActiveX controls, which represent a specific way of implementing ActiveX technologies. 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.
Unique identifier or location of a web page. Also called a Web Address or URL (Uniformed Resource Locator)
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.
American National Standards Institute. The U.S. standards organization.
Apache Web Server
Often referred to as simply Apache, a public-domain open source Web server developed by a loosely-knit group of programmers. The first version of Apache, based on the NCSA httpd Web server, was developed in 1995.
Core development of the Apache Web server is performed by a group of about 20 volunteer programmers, called the Apache Group. However, because the source code is freely available, anyone can adapt the server for specific needs, and there is a large public library of Apache add-ons. In many respects, development of Apache is similar to development of the Linux operating system.
The original version of Apache was written for UNIX, but there are now versions that run under OS/2, Windows and other platforms.
The name is a tribute to the Native American Apache Indian tribe, a tribe well known for its endurance and skill in warfare. A common misunderstanding is that it was called Apache because it was developed from existing NCSA code plus various patches, hence the name a patchy server, or Apache server
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.
Application ServerAlso called an appserver. A program that handles all application operations between users and an organization’s backend business applications or databases. Application servers are typically used for complex transaction-based applications. To support high-end needs, an application server has to have built-in redundancy, monitors for high-availability, high-performance distributed application services and support for complex database access.
A program that enables you to search for files anywhere on the Internet by filename.
(1) To copy files to a long-term storage medium for backup. Large computer systems often have two layers of backup, the first of which is a disk drive. Periodically, the computer operator will archive files on the disk to a second storage device, usually a tape drive.
On smaller systems, archiving is synonymous with backing up.
(2) To compress a file.
The precursor to the Internet, ARPANET was a large wide-area network created by the United States Defense Advanced Research Project Agency (ARPA). Established in 1969, ARPANET served as a testbed for new networking technologies, linking many universities and research centers. The first two nodes that formed the ARPANET were UCLA and the Stanford Research Institute, followed shortly thereafter by the University of Utah.
(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.
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.
The process of identifying an individual, usually based on a username and password. In security systems, authentication is distinct from authorization , which is the process of giving individuals access to system objects based on their identity. Authentication merely ensures that the individual is who he or she claims to be, but says nothing about the access rights of the individual.
Audio/Video Interleave. Microsoft’s video for Window’s standard.
Main high-speed network connections which together comprise the Internet. Backbone connections are installed, operated, and maintained by major telecommunications companies like Sprint, MCI, or AT&T.
(1) The amount of data that can be transferred over a 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.
(2) Bandwidth is also synonomous with the term Data Transfer and is used by many hosting companies to refer to the aggregate total of data (in MB) that is allowed to by downloaded or uploaded into your account in a given month
The Base 2 number system. Important for computers as chips and memory are designed with binary-based registers.
FTP client mode used to transfer binary files (multimedia files, executables and other data files). Not suitable for transferring normal text files.
(Binary DigIT) the smallest unit of information, comprising of either a 1 or 0.
The speed at which bits are transmitted over a communication link. Expressed in bits per second (bps).
Be Right Back
Sending a packet to all machines on the network.
Short for Web browser, a software application used to locate and display Web pages. The two most popular browsers are Netscape Navigator and Microsoft Internet Explorer. Both of these are graphical browsers, which means that they can display graphics as well as text. In addition, most modern browsers can present multimedia information, including sound and video, though they require plug-ins for some formats.
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.
By The Way
A modem designed to operate over cable TV lines. Because the coaxial cable used by cable TV provides much greater bandwidth than telephone lines, a cable modem can be used to achieve extremely fast access to the World Wide Web.
Cascading Style Sheets (CSS)
A feature of HTML that gives both Web site developers and users more control over how pages are displayed. With CSS, designers and users can create style sheets that define how different elements, such as headers and links, appear. These style sheets can then be applied to any Web page.
The term cascading derives from the fact that multiple style sheets can be applied to the same Web page. CSS was developed by the W3C.
Comite Consultatif International Telegraphique et Telephonique (International Telegraph and Telephone Consultative Committee). International telecommunication standards body.
(Conseil Europeen pour la Recherche Nucleaire) A nuclear research laboratory where the World Wide Web was invented.
Digital ID used for SSL transactions. It includes owner’s public key, the name of the owner, the issuer, hostname, and the expiration date.
Abbreviation of Common Gateway Interface, a specification for transferring information between a World Wide Web server and a CGI program. A CGI program is any program designed to accept and return data that conforms to the CGI specification. The program could be written in any programming language, including C, Perl, Java, or Visual Basic.
CGI programs are the most common way for Web servers to interact dynamically with users. Many HTML pages that contain forms, for example, use a CGI program to process the form’s data once it’s submitted. Another increasingly common way to provide dynamic feedback for Web users is to include scripts or programs that run on the user’s machine rather than the Web server. These programs can be Java applets, Java scripts, or ActiveX controls. These technologies are known collectively as client-side solutions, while the use of CGI is a server-side solution because the processing occurs on the Web server.
One problem with CGI is that each time a CGI script is executed, a new process is started. For busy Web sites, this can slow down the server noticeably. A more efficient solution, but one that it is also more difficult to implement, is to use the server’s API, such as ISAPI or NSAPI. Another increasingly popular solution is to use Java servlets.
A directory on the server where the executable CGI scripts reside.
A computer program that requests a service from a server program, usually over the network.
Connecting many computers or servers and making them appear as one machine. This is done to increase reliability and performance.
A product created by Allaire Corporation of Cambridge, Mass. (in 2001, Allaire merged with Macromedia) that includes a server and a development toolset designed to integrate databases and Web pages. With Cold Fusion, a user could enter a zip code on a Web page, and the server would query a database for information on the nearest movie theaters and present the results in HTML form. Cold Fusion Web pages include tags written in Cold Fusion Markup Language (CFML) that simplify integration with databases and avoid the use of more complex languages like C++ to create translating programs.
A utility, provided by Web Hosting companies to their clients, that allows a client to log in to their account and perform a number of account maintenance functions (billing information, e-mail accounts, ftp accounts, etc)
A message given to a Web browser by a Web server. The browser stores the message in a text file. The message is then sent back to the server each time the browser requests a page from the server. The main purpose of cookies is to identify users and possibly prepare customized Web pages for them. When you enter a Web site using cookies, you may be asked to fill out a form providing such information as your name and interests. This information is packaged into a cookie and sent to your Web browser which stores it for later use. The next time you go to the same Web site, your browser will send the cookie to the Web server. The server can use this information to present you with custom Web pages. So, for example, instead of seeing just a generic welcome page you might see a welcome page with your name on it.
Central Processing Unit. The actual “computer” that executes programs on a machine.
Also known as spider, an automated software that retrieves webpages and follows the hyperlinks contained in them. Used to generate indexes used by search engines.
In Web Hosting parlance, data transfer (also called Bandwidth) typically refers to the amount of data that is permitted to be downloaded per month, usually expressed in MB. A web hosting account with 1000 MB transfer will allow users to stream or download any number of files provided the aggregrate data does not exceed 1000 MB for the month.
Data in a structured format stored on a 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.
In the Web hosting business, a dedicated server is typically a rented service. The user rents the server, software and an Internet connection from the Web host.
Short for Domain Name System (or Service or Server), an Internet service that translates domain names into IP addresses. Because domain names are alphabetic, they’re easier to remember. The Internet however, is really based on IP addresses. Every time you use a domain name, therefore, a DNS service must translate the name into the corresponding IP address.
The DNS system is, in fact, its own network. If one DNS server doesn’t know how to translate a particular domain name, it asks another one, and so on, until the correct IP address is returned.
Domain name is an easy-to-remember address that can be translated by DNS into server’s IP address. Domain names are hierarchical. Domain’s suffix indicates which TLD (top level domain) it belongs to, for example .com, .gov, .org, .net, or .jp. Recently ICANN (Internet Corporation for Assigned Names and Numbers) added several new TLDs, like .biz, .pro., and .museum.
Digital Subscriber Line. A technology that allows high-speed internet connections to the Internet over phone lines.
Using web and Internet technologies in conducting the business activities. Also expanding end enhancing traditional business practices by means of the Internet.
(Frequently Asked Question) Lists of frequently asked questions and answers to them are used as a way of sharing knowledge on the web. They are a very good way of finding solutions to different problems. Some companies include them in their websites to minimize the number of Customer Support inquiries.
(Federal Communications Commission). U.S.A. telecommunications regulatory organization. It controls standards that pertain to electronic and electromagnetic transmission and also licenses the frequencies and bandwidth for the commercial use.
Fibre Optic Cable
A cable used for transmitting data as a light wave. A fiber optic cable is composed of one or more optical fibers. It is more expensive that copper wire, but offers higher transmission speeds and over larger distances.
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.
A UNIX program that takes an e-mail address as input and returns information about the user who owns that e-mail address. On some systems, finger only reports whether the user is currently logged on. Other systems return additional information, such as the user’s full name, address, and telephone number. Of course, the user must first enter this information into the system. Many e-mail programs now have a finger utility built into them.
A system designed to prevent unauthorized access to or from a private network. Firewalls can be implemented in both hardware and software, or a combination of both. Firewalls are frequently used to prevent unauthorized Internet users from accessing private networks connected to the Internet, especially intranets. All messages entering or leaving the intranet pass through the firewall, which examines each message and blocks those that do not meet the specified security criteria.
An insulting email message sent to an individual as punishment for not adhering to the netiquette. Can be sometimes seen in the newsgroups or on internet message boards.
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.
Short for File Transfer Protocol, the protocol for exchanging files over the Internet. FTP works in the same way as HTTP for transferring Web pages from a server to a user’s browser and SMTP for transferring electronic mail across the Internet in that, like these technologies, FTP uses the Internet’s TCP/IP protocols to enable data transfer.
FTP is most commonly used to download a file from a server using the Internet or to upload a file to a server (e.g., uploading a Web page file to a server).
Major browser also have FTP capability.
(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 but is limited to 256 colors.
2 to the 30th power (1,073,741,824) bytes. One gigabyte is equal to 1,024 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.
Base16 numbering system. The hexadecimal system is useful because it can represent every byte (8 bits) as two consecutive hexadecimal digits. It is easier for humans to read hexadecimal numbers than binary numbers. For example FF in hexadecimal is 11111111 in binary or 255 in decimal.
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).
Main web page on a website, usually with an introduction and links to other sections of the site. This is the page that is initially displayed when user makes a request for a particular domain name.
A networked computer dedicated to providing a certain kind of service. Most hosts on the internet are web servers (a type of host).
Short for HyperText Markup Language, the authoring language used to create documents on the World Wide Web.
HTML defines the structure and layout of a Web document by using a variety of tags and attributes. The correct structure for an HTML document starts with <HTML><HEAD>(enter here what document is about) and ends with </BODY></HTML>. All the information you’d like to include in your Web page fits in between the <BODY> and </BODY> tags.
There are hundreds of other tags used to format and layout the information in a Web page. Tags are also used to specify hypertext links. These allow Web developers to direct users to other Web pages with only a click of the mouse on either an image or word(s).
Short for HyperText Transfer Protocol, the underlying protocol used by the World Wide Web. HTTP defines how messages are formatted and transmitted, and what actions Web servers and browsers should take in response to various commands. For example, when you enter a URL in your browser, this actually sends an HTTP command to the Web server directing it to fetch and transmit the requested Web page.
Hyperlink (or link)
A special type of database system, invented by Ted Nelson in the 1960s, in which objects (text, pictures, music, programs, and so on) can be creatively linked to each other. When you select an object, you can see all the other objects that are linked to it. You can move from one object to another even though they might have very different forms.
A special type of database system, invented by Ted Nelson in the 1960s, in which objects (text, pictures, music, programs, and so on) can be creatively linked to each other. When you select an object, you can see all the other objects that are linked to it. You can move from one object to another even though they might have very different forms.
(Institute of Electrical and Electronics Engineers). Organization that ensures that electronic devices produced by different companies can interoperate. IEEE developed the 802 family of standards that govern computer networks.
Short for Internet Information Server, Microsoft’s Web server that runs on Windows NT platforms. In fact, IIS comes bundled with Windows NT 4.0. Because IIS is tightly integrated with the operating system, it is relatively easy to administer. However, currently IIS is available only for the Windows NT platform, whereas Netscape’s Web servers run on all major platforms, including Windows NT, OS/2 and UNIX.
An image displayed on a 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.
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.
In My Humble Opinion (or: In My Honest Opinion)
In My Opinion
A global network connecting millions of computers. More than 100 countries are linked into exchanges of data, news and opinions.
Unlike online services, which are centrally controlled, the Internet is decentralized by design. Each Internet computer, called a host, is independent. Its operators can choose which Internet services to use and which local services to make available to the global Internet community.
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.
Short for Internet Network Information Center, a registered service mark of the U.S. Department of Commerce and now a defunct entity. InterNIC began as a collaborative project between AT&T and Network Solutions, Inc. (NSI) supported by the National Science Foundation.
The InterNIC is currently an informational Web site established to provide the public with information about domain name registration. ICANN now oversees the domain name registration industry.
A part of an organization’s network that is private. Only authorized individuals have access to the intranet.
Abbreviation of Internet Protocol, pronounced as two separate letters. IP specifies the format of packets, also called datagrams, and the addressing scheme.
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 18.104.22.168. The current version of IP is IPv4. A new version, called IPv6 or IPng, is under development.
Internet Relay Chat. Multi-user chat service. IRC users can go into public or private channels to discuss a topic or transfer files. IRC servers are connected into networks. The most popular IRC client program is mIRC. Many hosts are wary of letting customers access IRC because of a possibility of a denial of service attack on the whole network.
(International Organisation for Standardisation). An Geneva-based international organization that develops and publishes various international standards.
Internet Service Provider. A company that provides its subscribers with Internet access. Customers have a username and a password and can dial-up or use a cable or DSL line to connect to ISP’s network which is connected to the Internet. The biggest ISP is AOL.
(International Telecommunication Union). (Formerly CCITT). Another international standards body concerned with telecommunications.
Sun’s popular programming language. Java is a platform-independent (at least in theory), 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’s syntax is similar to that of C++.
Java class files
The file or set of files that contain the code for a Java applet.
Servlets are programs written in Java that run on a Web server and can produce dynamic pages. Also see JSP.
Java Virtual Machine (JVM, Java Runtime Environment)
A set of programs that allow for Java applets to be run on a particular computer system.
Java Database Connectivity – a mechanism allowing Java applets to access different databases.
Short for Joint Photographic Experts Group, and pronounced jay-peg. JPEG is a lossy compression technique for color images. Although it can reduce files sizes to about 5% of their normal size, some detail is lost in the compression.
Java Server Pages. Extension of Java Servlet technology for combining Java server-side programs and HTML. JSP pages have an extension .jsp.
Kilobits per second. 1Kbps = 1024bps.
In decimal systems, kilo stands for 1,000, but in binary systems, a kilo is 1,024 (2 to the 10th power). Technically, therefore, a kilobyte is 1,024 bytes, but it is often used loosely as a synonym for 1,000 bytes
Local Area Network. A network of devices (computers, printers, hubs) occupying a small area. Usually LANs do not span more than one building. LANs are very fast compared to WANs.
(1) Another name for a connection. Sometimes refers to a physical line.
(2) Abbreviated form of the term hyperlink.
Latent Semantic Indexing
A document indexing process, used by Search Engines, that records which keywords a document contains and examines the document collection as a whole to see if any other documents contain the same keywords. LSI considers documents that have many common words to be semantically close, and those with fewer in common to be semantically distant. When an LSI-indexed database is searched it looks for similitarity values it has calculated for every content word, and returns documents it thinks best fit the query. LSI does not require an “exact match” to return useful results because two documents may be semantically close even if they don’t share a particulary keyword.
A public-domain UNIX-like operating system first developed by Linus Torvalds. Linux and FreeBSD are very often used by hosting companies as their operating systems for web servers as it is an inexpensive and highly stable/secure OS.
To make a computer system or network recognize you so that you can begin a computer session.
Laughing Out Loud
A compression scheme is loseless if no information is discarded during compression.
Lossy compression discards some information during compression. Useful when degradation of quaility is acceptable to dramatically reduce size.
Media Access Control.
Short for Media Access Control address, a hardware address that uniquely identifies each node of a network.
A way of having a group discussion with list subscribers by email. Emails are sent to all list subscribers. Popular mailing list programs, like Listserv and Majordomo, allow for automated subscription and un-subscription from a mailing list. Some hosting plans allow creation of mailing lists.
The Internet host (together with the appropriate software) that is used to send, receive and forward email messages.
MegaBytes (MB) per second, 1 MB = 1,048,576 bytes or 1024 kilobytes.
Megabits (Mb) per second, 1Mb = 1,048,576 bits
1MB = 1024 KiloBytes = 1,048,576 (2 to the 20th power) bytes
MegaHertz = 1.000.000 Hertz. 1 Hertz is a cycle per second.
(Multipurpose Internet Mail Extensions) a method of including binary data and other multimedia content within email messages.
A 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.
MOdulator-DEModulator. A device used to transform digital data sent by a computer to analog format suitable for transmission over a transmission line. It also transforms analog signals back to the digital form.
An extremely popular lossy audio compression format for audio files.
(Motion Picture Experts Group) video compression format for movies or animations.
mSQL (Mini SQL)
Light-weight relational database.
Pronounced “my ess cue el” (each letter separately) and not “my SEE kwill.” MySQL is an open source RDBMS that relies on SQL for processing the data in the database. MySQL provides APIs for the languages C, C++, Eiffel, Java, Perl, PHP and Python. In addition, OLE DB and ODBC providers exist for MySQL data connection in the Microsoft environment. A MySQL .NET Native Provider is also available, which allows native MySQL to .NET access without the need for OLE DB.
MySQL is most commonly used for Web applications and for embedded applications and has become a popular alternative to proprietary database systems because of its speed and reliability. MySQL can run on UNIX, Windows and Mac OS.
MySQL is developed, supported and marketed by MySQL AB. The database is available for free under the terms of the GNU General Public License (GPL) or for a fee to those who do not wish to be bound by the terms of the GPL.
Informal set of rules that should be followed when using internet services like email, message boards and newsgroups. Describes what it means to be “well behaved” while interacting with other people online.
Officially called Netscape Communications Corporation, Netscape was founded by James H. Clark and Marc Andreessen (creator of Mozilla) in 1994 and was acquired by AOL in 1999. It revolutionized the computer software market by giving away for free its popular Navigator Web browser until it had acquired an overwhelming market share for this category of software. The term Netscape is often used as the name of the company’s browser, not the company itself.
A virtual Internet place where people exchange thoughts, ideas and interests, and amuse themselves by means of text messages.
(Network News Transfer Protocol) An Internet protocol that describes how the newsgroups messages are distributed, stored, posted and retrieved.
Optical Carrier transmission speeds, used in fiber optic networks conforming to SONET standard. OC-1 is 51.85 Mbps. Higher levels are multiples of that speed.
(Open Database Connectivity) A standard allowing applications to access different databases in an uniform way.
The state of a computer or any other device when it is not connected to the network (i.e. it is not online).
Tha state of a computer when it is connected to the network and communicate with other machines.
A software heart of the computer. It is a set of programs that manage the hardware resources of a computer, provide the environment for application programs to run and provide the user interface. Most known operating systems are: different flavors of Unix (SunOs, HP-UX, Irix, FreeBSD, Linux,…), MacOS and Windows.
(Open System Interconnection). A network standard developed by ISO and CCITT. It describes the way in which protocols of different layers communicate. This enables machines of different vendors to communicate over the network.
Name for a basic web document. Websites usually consist of many (web) pages.
Open source CGI scripting programming language. Written in 1987. Still one of the most popular web programming languages mostly due to its powerful text-manipulation facilities. A huge number of Perl scripts are available for download.
PHP is an free, open-source server-side scripting language. PHP code can be embedded in HTML. PHP files usually have extensions like .php or .php3. PHP language style is similar to C and Java. Other popular server-side scripting languages are ASP, Perl, ColdFusion, TCL, Python, and JSP.
PKZIP or PKUNZIP
Popular compression and decompression programs.
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.
Post Office Protocol. Popular and simple email retrieval standard. All messages are downloaded at the name time and can only be manipulated on a client machine. Current version is POP3.
1) An interface on a computer to which you can connect a device. Personal computers have various types of ports. Internally, there are several ports for connecting disk drives, display screens, and keyboards. Externally, personal computers have ports for connecting modems, printers, mice, and other peripheral devices.
(2) In TCP/IP and UDP networks, an endpoint to a logical connection. The port number identifies what type of port it is. For example, port 80 is used for HTTP traffic. Routers and firewalls typically block traffic over most ports allowing only those applications to run across a network that are “safe” to allow the outside world.
(Point to Point Protocol) A network protocol widely used to connect computers to the Internet. Most often used on a telephone line.
A set of rules by following which two parties can communicate. The TCP/IP protocol suite is the basis of todays Internet.
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.
Level 0 implements data striping where file blocks are written to separate drives. Does not provide fault tolerance, because failure of one drive will result in data loss.
Level 1 implements data mirroring. Data is duplicated on two drives either through software or hardware. Provides faster read performance than a single drive.
Level 2 – not used in practice. Data is split at bit level at written to multiple drives.
Level 3 – requires at least 3 drives. Data block is striped at byte level across drives and error correction codes (parity info) is recorder on another drive. Provides fault tolerance but slower writing performance.
Level 4 – Similar to Level 3 but provides faster performance because it uses blocks for striping.
Level 5 – Similar to Level 4 but improves performance but also striping parity info across multiple drives.
Level 6 – Similar to Level 5 but also uses second parity scheme for better fault tolerance.
Level 7 – Proprietary RAID design by Storage Computer Corporation. Faster than other levels because it uses multiple levels of cache and asynchronous I/O transfers.
In addition multiple RAID levels can be combined to improve performance or reliability.
Resellers are usually smaller companies that still try to build their customers base. They don’t own the server with user accounts but can perform most administrative functions.
A standard connector that is used to connect to the telephone line. Also known as a phone jack.
A standard connector that is used to connect to the Ethernet network. Looks like a big phone jack.
Rolling On the Floor Laughing
A network device (can be a dedicated computer) that is used to connect two or more networks together and route packets between them.
A public key cryptosystem developed by Ron Rivest, Adi Shamir, and Leonard Adleman. It can be used to encrypt session keys and to generate digital certificates.
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.
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.
A program that searches documents for specified keywords and returns a list of the documents where the keywords were found. Although search engine is really a general class of programs, the term is often used to specifically describe systems like Google and Yahoo that enable users to search for documents on the World Wide Web and USENET newsgroups.
Typically, a search engine works by sending out a spider to fetch as many documents as possible. Another program, called an indexer, then reads these documents and creates an index based on the words contained in each document. Each search engine uses a proprietary algorithm to create its indices such that, ideally, only meaningful results are returned for each query.
A compressed (archived) file that is also an executable program. The file(s) that were archived are extracted automatically when the program is run without the need for an archive utility like WinZip.
A networked computer that handles client requests for resources. Most servers on the Internet are web servers.
All the data exchange between two terminals, starting when the connection is established and ending when connection terminates.
Initial fee charged by a host to set up your hosting account.
Secure HTTP. A version of HTTP protocol that uses encryption to assure that the traffic between the server and the browser cannot be eveasdropped on. Should be considered mandatory for all e-commerce applications.
Characters used in text-only communications to convey emotions. Example :O :(…
Simple Mail Transfer Protocol. The predominant protocol used to transfer email messages across the Internet mail servers.
A normal paper mail delivered by the Post Office.
(Simple Network Management Protocol). A most widespread protocol used for network management.
Unsolicited email sent in mass quantities to multiple receipents, most often for marketing purposes.
An automated software that retrieves webpages and follows the hyperlinks contained in them. Used to generate indexes used by search engines.
Structured Query Language. 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.
Secure Shell. Developed by SSH Communications Security, it is a standard for encrypted terminal Internet connections. SSH programs provide strong authentication and encrypted communications, replacing less secure access methods like telnet.
Server-Side Includes. Instructs 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.
Short for Secure Sockets Layer, a protocol developed by Netscape for transmitting private documents via the Internet. SSL works by using a private key to encrypt data that’s transferred over the SSL connection. Both Netscape Navigator and Internet Explorer support SSL, and many Web sites use the protocol to obtain confidential user information, such as credit card numbers. By convention, URLs that require an SSL connection start with https: instead of http:
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.
Playing multimedia files (audio and video) from an online file without requiring a full download. Audio and video are compressed but they still may require a lot of bandwidth. Popular streaming formats inclue Real Media, Quicktime, and Windows Media.
Using world wide web is often referred to as “surfing the web”.
A switch is a network device that forwards packets to other devices on the same networks. Switches are more intelligent than hubs and typically place each node in its own broadcast domain eliminating collisions and improving overall performance.
Dedicated telecommunications line providing 1.5 Mbps of bandwidth. Consists of 24 individual channels 64 Kbps each, that can be configured for voice or data transmission. T1 lines can be leased by businesses that required a dedicated Net connection of with higher reliability than a DSL and faster than an ISDN line but are still quite expensive.
Dedicated telecommunications line providing 44 Mbps of bandwidth. T3 lines are often used by ISPs to connect to the Internet backbone.
Abbreviation of Transmission Control Protocol, and pronounced as separate letters. TCP is one of the main protocols in TCP/IP networks. Whereas the IP protocol deals only with packets, TCP enables two hosts to establish a connection and exchange streams of data. TCP guarantees delivery of data and also guarantees that packets will be delivered in the same order in which they were sent.
Short for Transmission Control Protocol/Internet Protocol, the suite of communications protocols used to connect hosts on the Internet. TCP/IP uses several protocols, the two main ones being TCP and IP. TCP/IP is built into the UNIX operating system and is used by the Internet, making it the de facto standard for transmitting data over networks.
Character-based protocol for connecting with remote systems. Still popular among hosts, but it is being replaced by much more secure SSH access.
1024 gigabytes = (2 raised to the 40th power bytes!)
Short for top-level domain, and refers to the suffix attached to Internet domain names. There are a limited number of predefined suffixes, and each one represent a top-level domain. .com, .net, .gov, and .org are examples of TLD’s.
A computer program that lists network hosts visited by a packed on the way to its destination. Very useful for network debugging.
Data packets being transmitted over a network.
A pair of wires twisted one around the other. Very common in the networking applications.
A 16 bit ISO 10646 character set. It can accommodate more characters that ASCII, thus allowing for easier internationalization.
A family of multi-user operating systems, first developed by AT&T Bell Laboratories in the 1970s and then licensed to many universities. A basis for Linux, a very popular operating system among web hosts.
Uninterruptible Power Supply. UPS kicks in if power is lost allowing servers and other critical infrastructure to keep operating until generators kick in or the administrators shut them down.
(Uniform Resource Locator) is a way of addressing used for world wide web. An URL consist of the type of service (protocol), then the host name and then the file on the host.
Network of all the newsgroups in the Internet.
An stand-alone application used to display files of different formats. For example a QuickTime move viewer or a JPG file viewer.
A malicious program written to disrupt computer systems.
(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.
World Wide Web Consortium. An international industry consortium that develops standards for the world wide web.
An audio file format. Very accurate, but offers no compression, thus resulting in very large files.
A person responsible for the maintenance of a particular website.
An Internet service allowing to obtain the information about a domain name.
Wide Area Network (WAN)
A group of LAN’s interconnected across a campus or region.
World Wide Web
Extensible Markup Language. A meta-language, abbreviated version of SGML, used to specify other document types used on the Web. Accepted as a format in 1998 to replace dependence on HTML extensions. MSIE 5.5 and Netscape 6 both support XML.
Your Mileage May Vary
A popular compression format that allows files to be compressed (or shrunk) to allow for easier file sharing.