Web Hosting Glossary of Terms

Applet
An applet is a small executable module, that normally doesn’t have the complete features and user interface of a normal application. Java is the language most commonly associated with applets. An applet is like a small piece of executable code that needs a full application to contain it. The applet runs inside of the application in a “sand box” or “virtual machine,” which is a set of computer resources and instructions that make up an environment for the applet’s execution.

ASP (Active Server Pages)
Microsoft NT scripting language which allows YOU to design web pages that can make displaying, manipulating and editing databases quick and easy.

Audio Streaming
The process of providing audio clips or content via a web page.

Backbone
A high-speed line or series of connections that forms a major pathway within a network. The term is relative as a backbone in a small network will likely be much smaller than many non-backbone lines in a large network.

Bandwidth
How much data you can send through a connection. Usually measured in bits-per-second. A full page of English text is about 16,000 bits. A fast modem can move about 15,000 bits in one second. Full-motion full-screen video would require roughly 10,000,000 bits-per-second, depending on compression.

CGI
(Common Gateway Interface) — A set of rules that describe how a Web Server communicates with another piece of software on the same machine, and how the other piece of software (the “CGI program”) talks to the web server. Any piece of software can be a CGI program if it handles input and output according to the CGI standard. Usually a CGI program is a small program that takes data from a web server and does something with it, like putting the content of a form into an e-mail message, or turning the data into a database query. You can often see that a CGI program is being used by seeing “cgi-bin” in a URL, but not always.

Co-location
Most often used to refer to having a server that belongs to one person or group physically located on an Internet-connected network that belongs to another person or group. Usually this is done because the server owner wants their machine to be on a high-speed Internet connection and/or they do not want the security risks of having the server on thier own network.

Cookie
A message given to a Web browser by a Web server. The browser stores the message in a text file called cookie.txt. 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.

The name cookie derives from UNIX objects called magic cookies. These are tokens that are attached to a user or program and change depending on the areas entered by the user or program. Cookies are also sometimes called persistent cookies because they typically stay in the browser for long periods of time.

Data Transfer
This is the amount of data that you are allowed to transfer with your account. Data is this case usually referrs to images, text, or anthing else that the web server must transfer to the user’s web browser. As a general rule 500 MB of data transfer is equivilant to about 20,000 page views.

Domain Name
The unique name that identifies an Internet site. Domain Names always have 2 or more parts, separated by dots. The part on the left is the most specific, and the part on the right is the most general. A given machine may have more than one Domain Name but a given Domain Name points to only one machine. For example, the domain names:

  • domain.com
  • search.domain.com
can all refer to the same machine, but each domain name can refer to no more than one machine.

Usually, all of the machines on a given Network will have the same thing as the right-hand portion of their Domain Names (matisse.net in the examples above). It is also possible for a Domain Name to exist but not be connected to an actual machine. This is often done so that a group or business can have an Internet e-mail address without having to establish a real Internet site. In these cases, some real Internet machine must handle the mail on behalf of the listed Domain Name.

Finger
An Internet software tool for locating people on other Internet sites. Finger is also sometimes used to give access to non-personal information, but the most common use is to see if a person has an account at a particular Internet site. Many sites do not allow incoming Finger requests, but many do.

FTP
(File Transfer Protocol) — A very common method of moving files between two Internet sites. FTP is a special way to login to another Internet site for the purposes of retrieving and/or sending files. There are many Internet sites that have established publicly accessible repositories of material that can be obtained using FTP, by logging in using the account name anonymous, thus these sites are called anonymous ftp servers.

Hosting Provider
An institution that provides web space to companies or individuals, usually for money.

HTTP
(HyperText Transport Protocol) — The protocol for moving hypertext files across the Internet. Requires a HTTP client program on one end, and an HTTP server program on the other end. HTTP is the most important protocol used in the World Wide Web (WWW).

IP NumberIP Number
(Internet Protocol Number) — Sometimes called a dotted quad. A unique number consisting of 4 parts separated by dots, e.g. 165.113.245.2

Every machine that is on the Internet has a unique IP number – if a machine does not have an IP number, it is not really on the Internet. Most machines also have one or more Domain Names that are easier for people to remember.

ISP (Internet Service Provider)
An institution that provides access to the Internet in some form, usually for money.

Megabyte
A million bytes. Actually, technically, 1024 kilobytes.

POP
Short for Post Office Protocol, a protocol used to retrieve e-mail from a mail server. Most e-mail applications (sometimes called an e-mail client) use the POP protocol, although some can use the newer IMAP (Internet Message Access Protocol).

There are two versions of POP. The first, called POP2, became a standard in the mid-80’s and requires SMTP to send messages. The newer version, POP3, can be used with or without SMTP.

Server
A computer, or a software package, that provides a specific kind of service to client software running on other computers. The term can refer to a particular piece of software, such as a WWW server, or to the machine on which the software is running, e.g.Our mail server is down today, that’s why e-mail isn’t getting out. A single server machine could have several different server software packages running on it, thus providing many different servers to clients on the network.

Server Side Includes (SSI)
Commands that can be included in web pages that are processed by the web server when a user requests a file. The command takes th form <!–#include virtual=”/path/to/file”–>. For example, a common use for SSI commands is to insert the date or last modified date on a file.

SMTP
(Simple Mail Transport Protocol) — The main protocol used to send electronic mail on the Internet.

SMTP consists of a set of rules for how a program sending mail and a program receiving mail should interact.

Almost all Internet email is sent and received by clients and servers using SMTP, thus if one wanted to set up an email server on the Internet one would look for email server software that supports SMTP.

SSL
(Secure Sockets Layer) — A protocol designed by Netscape Communications to enable encrypted, authenticated communications across the Internet.

SSL used mostly (but not exclusively) in communications between web browsers and web servers. URL’s that begin with “https” indicate that an SSL connection will be used.

SSL provides 3 important things: Privacy, Authentication, and Message Integrity.

In an SSL connection each side of the connection must have a Security Certificate, which each side’s software sends to the other. Each side then encrypts what it sends using information from both its own and the other side’s Certificate, ensuring that only the intended recipient can de-crypt it, and that the other side can be sure the data came from the place it claims to have come from, and that the message has not been tampered with.

T-1
A leased-line connection capable of carrying data at 1,544,000 bits-per-second. At maximum theoretical capacity, a T-1 line could move a megabyte in less than 10 seconds. That is still not fast enough for full-screen, full-motion video, for which you need at least 10,000,000 bits-per-second. T-1 is the fastest speed commonly used to connect networks to the Internet.

T-3
A leased-line connection capable of carrying data at 44,736,000 bits-per-second. This is more than enough to do full-screen, full-motion video.

Telnet
The command and program used to login from one Internet site to another. The telnet command/program gets you to the login: prompt of another host.

UNIX
A computer operating system (the basic software running on a computer, underneath t things like word processors and spreadsheets). UNIX is designed to be used by many people at the same time (it is multi-user) and has TCP/IP built-in. It is the most common operating system for servers on the Internet.

URL
(Uniform Resource Locator) — The standard way to give the address of any resource on the Internet that is part of the World Wide Web (WWW). A URL looks like this:
http://www.yahoo.com/

The most common way to use a URL is to enter into a WWW browser program, such as Netscape, or Lynx.

Video Streaming
The process of providing video data or content via a web page.