Web Intro:How the Internet Works

The internet is a large number of computers connected to each other via high speed lines. Some of these are servers, they have information such as graphics, text, music, etc. Other computers connected to the internet are like you and I connecting to the internet, they want to look at , hear or in some way use the information on the servers. These users like you and I are called clients. Its sort of like the servers are phone answering machines and the clients are people who call and hear the message on the answering machine. The connection for the internet is much like phone connections but typically capable of much faster transmission of information. Individual users are often connected to the internet through their school or work. At home you cannot connect directly to the internet you need to connect via an ISP, Internet Service Provider such as AOL, Netconnection, Compuserve, RoadRunner, etc. who like CSUB have direct connections to the internet. Typical connections are by phone line and a 56k modem are a broad band, DSL or cable modem. To obtain the speed and utilize many of the web resources such as music and video you will need a fast/broad band connection, a DSL or cable modem connection. These faster connections allow communication and the distribution and sharing of resources available between interconnected computers in a home network. Internet connections now exist throughout the world.

How "home pages" on the world wide web work: Files to be displayed, played, etc. are located on a web server that is connected to the internet and has an internet address, a URL (Universal Resource Locator). These files may contain text, pictures, sounds, movies, games or even virtual reality displays.

To see, hear, download are play these files one must have a browser on your computer that can access the server and download the files and display or play them on your computer. The most common browsers Firefox, Netscape and Microsoft Internet Explorer can display most but not all types of files. You may need on occassion to download a file, a media player for example, to display new types of files. One example is Google Video Player to play downloaded UTUBE videos.

In the box on the left are types of files that can be accessed by a browser such as Firefox, Netscape or Explorer:

	Welcome.html is a file that contains html commands that contain the text and the format commands for displaying graphics and playing sounds and video, a web page,
	/~jross/graphics/jross2.gif is a graphic in the "gif" format. It will display a picture when accessed by a web page..

The other files are sounds, movies, 3D graphics, etc. The Box on the right displays possible software on the client (browser) side of a connection. These files are browsers such as Firefox, Netscape and Explorer and various helper files that enable the browser to play sounds, movies, etc. The other files are programs such as NCSA Telnet that let one connect to a distant computer.

Domains/Extensions: The internet is organized logically into domains usually referred to as the extension, the letters following the "." in the name of a web site. There are two letter international extensions/domains indicating country, and the typical three letter extension as well as the new (but not currently in use) three and four letter extensions indicating type of group a web site is controlled by. Extensions in general are indicative of the content and purpose of a web page and may be useful in considering the credibility of a web page but not a guarentee.

Anchor also called a bookmark by Microsoft is the destination of a hyperlink within a Web page. Anchors are common on single Web pages containing lots of text where the text section titles appear at the top of the page and clicking the link causes the browser to jump down the page and display the selected portion of text. The Table of Contente at the beginning of this page links to anhors in the page.

ADSL/DSL Asynchronous Digital Services Line, a fast method of digital communication using standard telephone lines with enhancement hardware at the send and receive end. Speeds on the internet are currently up to 56 kilobits per second with a standard modem (actual speed is in the 30's) at a a cost of approximately $10 per month. ADSL offers a data-only service at speeds ranging from about 140 Kbps to more than 1 megabit per second, using a high-speed modem and a phone line. Current costs are about $40-$50 a month, plus installation fees, often waved, of several hundred dollars. See also ISDN, T1

ANARCHIE [Mac] an older program designed for easy transfer (see FTP) of files between computers (see FTP, FETCH)

AT COMMAND SET: The standard commands used to send instructions to a modem. The letters AT stand for ATtention and are usually followed by one or more commands to the modem. Developed for modem use by Hayes Microcomputer Products. Modems that use the AT command set and a Hayes-patented modem-escape sequence are said to be Hayes compatible.

BAUD RATE: A measure of data-transmission speed. Baud equals the number of times per second the modem modulates the computer's signal. At low speeds such as 300 bps, 1 baud is roughly 1 bps. Baud rates are often used interchangeably with bps but are not exactly the same.

BITNET an early 1980 academic computing network with a gateway to the internet

BLOG/WEBLOG A web based journal or newsletter that is usually updated frequently and is intended for whoever might be interested. Blogs often are used as new sources, rumors about celebreties, etc. MySpace can be seen as a type of Blog.

BROWSER A program that resides on a personal computer, a client, on the web. Browsers download (bring HTML, pictures, video, and other files from a distant computer, the server, to your local computer) and displays or plays the text, pictures, sounds, movies, etc. The most common are Netscape, Microsoft Internet Explorer, Firefox, Mosaic and Opera all to some extent are based on Mosaic the original browser developed at The University of Illinois. The current versions can be downloaded free.

CABLE MODEM A modem attached to a coaxial cable television system. Cable modems can transmit data at 500
kilobytes a second, much faster than a typical computer modem that sends signals over telephone rated at 56 kilobytes a second (really 52 with overhead) but typically around 33 kilobytes a second.

ClIENT/SERVER a computer connection set-up in which most of the computers (clients) tend to share resources from one main computer (the server). The web operates this way with individual users being clients who access information from a server. For example a student at CSUB is a client of the CSUB web server HTTP://www.csub.edu.

CPS Characters per second. A measure of communications speed; 1 cps is roughly 8 bps.

DOMAIN(S) on the internet the last three letters of an Internet address represent the domain or particular section of the Internet e,g commercial-.com, education-.edu., US Government- gov; .Network Infrastructure Organizations net - .net, Non-profit Organizations-.org - ; military-.mil, country codes such as .ca for Canada, .fr for France, and .jp for Japan. See The Structure of the Internet above for more about domains

DSL Uses existing copper phone wiring to provide a fast connection to the Internet. DSL modem and filters are attached to both ends of the line to allow data to transmit over the wires at a far greater speed than the standard phone wiring. It also provides a constant connection to the Internet meaning there is no need to dial-in to your ISP each time you want to get online. A DSL line is convenient in that you only need one line to carry both voice and data signals (meaning you don't have to get a second phone line. The major problem with DSL is you must have a copper wire connection to the phone switch and you must live relatively close since DSL speed degrades with distance. Call your telephone service if you want to know if DSL will work for you.

Domains/Extensions (useful in considering the credibility of a web page but not a guarentee):
There are two letter international extensions, and the typical three letter extension as well as the new (but not currently in use) three and four letter extensions. Extensions in general are indicative about the source, content and purpose for a web page.

E-MAIL the exchange of letter like messages through computer networks and the internet.

ETHERNET a technique for connecting computers and other hardware into a LAN, local area network. The ethernet cable currently is category 5 referred to as Cat5, which carries 8 bits simultaneously over 8 wires.

FETCH [Mac] a program designed for easy transfer (see FTP) of files between computers (see FTP, ANARCHIE)

FTP File Transfer Protocol, procedures that allow/facilitate file exchanges between computers over the Internet. A software scheme for eliminating transmission errors when sending files. These schemes send data in small chunks called packets, then check each packet for errors. If the software detects an error, the protocol resends the packet. If no errors are detected, the next packet is sent. Common file-transfer programs include Fetch, WS_FTP which are used at CSUB.

FULL DUPLEX a mode of transmission in which data is sent in both directions simultaneously. Full duplex is the usual mode for the majority of data transmissions.

GIF (Graphics Interchange Format) A compressed graphics file format common on the Internet. The most common graphic format used on the web, can be displayed by most graphic capable browsers

GOPHER an early pre browser which assessed information on the internet. a hierarchical menu driven server created at the University of Minnesota that aids access to Internet services by acting as a pointer to resources. A campus, government agency as well as specific groups could set up a GOPHER to aid access to specific resources

HALF DUPLEX a mode of transmission in which data is sent in only one direction at a time. Most commonly used in fax transmission.

HANDSHAKE the sequence of signals that two modems exchange in order to establish the common speed and format used by the modem for data transmission. Listen to the changing beeps you modem makes when connection to your ISP

HOME PAGE Two meanings (1) the web page that your browser is set to open when started and (2) as related to a web site, refers to the main web page for a business, organization, person or simply the main page. This page usually opens when you go to the site without specifically naming the web page. If you go to HTTP://www,csub.edu the home page (actually named index.html or welcome.html) opens.

HTML editor an application (Pagemill, Microsoft FrontPage, Mozilla, Netscape Composer etc.) or add on to an application (Word 6, ClarisWorks, etc.) that aids in creating a new HTML, a web page, or converting an existing file to an HTML document, a web page.

HTML Hyper Text Markup Language, a simple nonproprietary text-based generic markup language for representing the design and contents of documents that World-Wide Web browsers can display. Formats are specified by tags. HTML+ is a set of modular extensions to HTML and has been developed to meet needs of information providers. The extensions include text flow around floating figures, fill-out forms, tables and mathematical equations, etc. XHTML, Extensible Hypertext Markup Language - A reformation of HTML 4.0 in XML 1.0. XHTML, is a new language for building web pages that has recently been proposed. HTML was invented by Tim Berners-Lee while at CERN, the European Laboratory for Particle Physics in Geneva.

HTTP (Hypertext Transport Protocol) A fast, stateless information-retrieval protocol designed to distribute information quickly to as many users as possible. Addresses for documents on the World-Wide Web usually begin with http://www similar to the "1" when calling long distance, before the server computer's name, as in:

HYPERLINK Embedded connections in text or images that take the user to another document (in Powerpoint, hypercard, Hyperstudio a link takes you to another slide or performs a function such as play music, download a document, etc. Typically in a web page the text or graphic, when clicked, transports your web-browser to another location to retrieve and display the information at that location. Hyperlinks for browsers are typically text, blue in color, and nearly always underlined. Pictures and graphics are also frequently hyperlinks. Some e-mail programs allow web addresses sent in e-mail messages to be double clicked to open the web browser and go to the web site. When creating a web page you specify the file and even the location within the file you are jumping to (1) absolute link, which gives the file's full network address (called a uniform resource locator, or URL). Whenever you have no control over the location of the file you are jumping to, you use an absolute link. (2) relative link, which gives the location of the file you are jumping to as it is located in relation to your document. You only use a relative link when you can control where the file you are jumping to is located. Generally that means you use relative links to jump to files you have available on your web server.

hypertext, hypermedia (see Hyperlink) text, pictures that link to other information allowing one to go through material in a nonlinear fashion, for example one might click on a term and get an explanation, picture, sounds, demonstration or go to a different section of the material

ISDN (Integrated Services Digital Network) A fast digital technology designed to replace less efficient analog telephone lines and modems. ISDN "modems" are actually 64 thousand to 128 thousand bits per second (128 kilobits). This can be divided into two voice lines, making it especially suitable for the communication needs of small businesses. You can call out on one line while surfing the Internet on a second line at 64 Kbps. In California only 56 kilobits per line is possible. See also ADSL, T1, TCI, DirecPC and

Internet (see also WWW)an international network connecting business (.com) military (.mil), research (.org), academic (.edu), etc. that provides communication, textual and numeric information, travel reservations, file transfer of shareware, etc.

ISP Internet Service Provider, a direct connection to the internet. Individuals connect through an ISP to obtain web services. You can call the ISP, connect through DSL or a LAN in order to use the internet. There are both commercial and non commercial ISPs. If you are connecting to the internet from home you will have to have to connect through an ISP. (Examples AOL, PacBell, NetConnection, Compuserve...)

JAVA A programming language capable of running on many platforms and used to add functions to a web page

JPEG (Joint Photographic Experts Group) Joint Photographic Experts Group. Commonly used to refer to a lossy compression technique, reducing the size of a graphic file by as much as 96%. Usually the best file format for photographs on the Web. One negative is that it does loose quality with repeated editing and saves.

LAN local area network (within one site); a connection of computer hardware (computers, printers, disk drives, internet connection). Data typically is transmitted over wires, ethernet/CAT5. It allows information and hardware sharing. See NETWORK and WAN

LYNX A very primitive browser by current standards. It was designed for slow modem speed and only for text display and linking. LYNX did not display pictures, movies or sounds.

MODEM modulate/demodulate, the device that allows one to use the phone line to communicate with other computers by converting computer data representation to a form, sounds, that can be sent and received through phone lines. Limited to 56 k speed and currently being replaced by DSL and Cable Modem

MOSAIC, MOZILLA, FIREFOX, NETSCAPE, EXPLORER: these browsers are all derivations of the original MOSAIC browser developed at the University of Illinois. With the proper Helper files connected these browsers can download and display pictures, movies, sounds and virtual reality files. The newest versions allow an ever increasing variation in formatting of displays.

MYSPACE, a social networking site that uses the Internet for online communication through an interactive network of photos, weblogs, user profiles, e-mail, web forums, and groups, as well as other media formats.

NETWORK Interconnected computer hardware (computers, printers, disk drives); data transmission over wires allowing information and hardware sharing, see LAN, WAN. The WWW/Internet is the largest computer network.

PEER To PEER a connection directly between computers that creates equal status between the computers

PERL Practical Extraction and Report Language, a language used to add database functionality to a web page

PROXY a proxy is used to control access to web sources. In k-12 schools a proxy is typically used to filter access to sites decided as unacceptable. At the CSUB library a proxy is used to control access to databases that are not for public use. (Lexus/Nexus for example has a contractual agreement that allows only faculty, staff and students access so a proxy is used.) Only one proxy is allowed at a time. A CSUB student who is accessing Lexus/Nexus will need to sign on with their Runner ID to access the proxy.

Helpers/Plugins: Small programs used to add functions to a larger program such as sound or graphic helpers used to add functionality (play sounds or display particular document formats, show quicktime or MPEG formatted movies) to browsers. You add these helpers to your browser to enable these tasks. RealRadio, Quicktime, Flash are examples. If you browser won't display or play web info you probably need to download and install a plugin for that type of file.

IM Instant Messaging chat rooms, AIM (AOL INstant Messaging, Yahoo Messenger, etc.), which notifies a user when a friend is online, allowing them to "converse" by exchanging text messages.

PPP Point-to-Point Protocol. This protocol is a way to connect your computer to the Internet over telephone lines. PPP is replacing an older protocol, SLIP

PROTOCOL a set of rules or standards on how to perform a task. They define common data structures for sending and receiving information. Protocols define such things as error-checking conventions and how data is formatted (e.g. FTP, SLIP, PPP, TCP/IP)

SERVER, a computer (PC or Mainframe) used to store applications, documents, music files, movies, etc. for use by other computers connected to it, see LAN, WAN INTERNET. Usually the hardware is maximized for communication rather then computation. Most computers can perform server tasks but less efficiently then a computer designed as a server. For web use servers must be directly connected to the web for anyone to see its files.

SGML Standard Generalized Markup Language, a metaformat that allows one to specify a wide range of document formats.

SOCIAL NETWORKING SITE a web site that facilates social interaction and communication through sharing of information, photographs, music, etc. [see Myspace]

T1 the standard communication connection method for large businesses, government, military and education (this is CSUB's interconnection). Typical speed is 1.5Mbps (millions of bits per second)

TAGS Formatting commands included in a web document to tell the browser how to display the page material

TCP/IP Transmission ControlProtocol / Internet Protocol, the standard used on the internet for connecting different types of networks and computers

URL Universal Resource Locator, the world wide web address of a home page, gopher site or e-mail address. A pointer to a file or resource available on the Internet; the Internet's shorthand for directions to Internet-bound resources, used most often with World-Wide Web browsers such as Firefox, Netscape, Microsoft Explorer. A typical URL is a web address such as:

USENET, NEWS a bulletin board that allows positing, retrieving, reading user messages. It is grouped by interest

VOIP Voice over Internet Protocol Using the internet, packet based networks, instead of the standard public switched telephone network to send voice data. Everyone is getting into this at this time (e.g. Skype))

WAIS Wide Area Information Server, a database on the internet where users can search for a term using a natural language quire

WAN wide area network; example is the network of the entire California State University system state-wide; used for communication, information and hardware sharing. In many ways the widest WAN would be the internet.

WIKIa "website that allows the visitors themselves to easily add, remove, and otherwise edit and change available content...an effective tool for mass collaborative authoring. The term wiki also can refer to the collaborative software itself (wiki engine) that facilitates the operation of such a Web site, or to certain specific wiki sites, including the computer science site (the original wiki) WikiWikiWeb and on-line encyclopedias such as Wikipedia." Wikipedia [2/19/07]

WWW World Wide Web, (see also Internet) the connection between computers throughout the world and the information available on these computers. A hypertext system for the exchange of information on the internet, originally designed for use by physicist at the CERN laboratory in Geneva

Three Letter Extension	Samples	Descriptions
.com	http://www.nabisco.com http://www.chevron.com http://www.marines.com (The business of enlistment.)	Commerce or Commercial
.org	http://www.graham-assn.org http://www.cancer.org	Non-Profit, charitible, political, etc. organization
.edu	http://www.csub.edu/ http://www.harvard.edu	Education or School
.gov	http://www.whitehouse.gov/ http://www.fbi.gov/	Government
.mil	http://www.army.mil http://www.usmc.mil	United States Military
.net	http://www.netxn.net/ http://account.netzero.net/	Network oriented such as ISP's Internet service providers. .
.uk	http://www.amazon.co.uk/ .uk = United Kingdom or Britain http://www.amazon.de/ .de = Deutschland or Germany http://www.bcsd.k12.ca.us .us =United States	2 Letter Country Extension (Used for countries designation.)
.xxx	This is for college students but warning the links below will be offensive so don't click if there is any chance you will be offended! http://www.cyberporn.xxx http://www.smut.xxx http://www.dirtymind.xxx	Pornographic Sites purposed for future use. They currently use commerce, ".com", extensions. So far not accepted as a domain since no one wants to define what is XXX material.
.biz, .info, .name, .pro, .coop, .aero, .museum	Please note that all URLs listed above were checked when this page was created. Also, please check each URL address for the inclusion, or exclusion, of the World Wide Web prefix "http://www".	New domains accepted by ICANN . Names are currently being registered. Current domains, click by GO! to see the list.

	http://en.wikipedia.org/wiki/History_of_the_Internet History of the internet
	http://www.netvalley.com/intval.html: More history of the Internet
	http://www.sfgate.com/cgi-bin/article.cgi?file=/chronicle/archive/2001/12/03/BU181003.DTL: Recent History to 2001
	InterNIC Information about how the webs's rules such as doman names work . "In January of 1993 the InterNIC was established as a collaborative project between AT&T, General Atomics and Network Solutions, Inc. and supported by three five-year cooperative agreements with the National Science Foundation. AT&T was to manage the InterNIC Directory and Database Services project; NSI was to manage the Registration Services project, and General Atomics was to manage the Information Services project."
	http://www.webopedia.com/ Source for definitions of internet terms
	http://www.switchboard.com/Internet_Service_Providers/Bakersfield/CA/16539-/yellowpages.htm Internet Service Providers for Bakersfield and Kern County. Search this site for ISP's. My personal local choices have been NetConnection for 56k connection, AT&T for DSL fast connection and of course Road Runner/Brighthouse local cable connection.

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