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Mid-Michigan Computer Consultants, Inc.
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Bay City, Michigan
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WEB BASICS
An introduction to the technology of the internet.
REVISED February 2004
MMCC is committed to providing quality information and services that are both efficient and effective. Part of that job is to help our clients understand the technology of the information age.
The INTERNET and the WORLD WIDE WEB, are complex, high tech systems that we use daily with no need to understand technically. They just work so the details are not necessary.
If, on the other hand, you're buying internet services, it can be helpful to understand at least the basics of how things are connected, who sells what, and how the pieces are put together.
The purpose of this article is to offer an overview of the major pieces of the puzzle. I start with a discussion of the components of the internet. You run a "web browser" on your computer. You're connected to the ineternet by an internet service provider. Web sites are out in the world on "web servers". The whole think is connected by the "internet".
The second section will talk about web sites and HTML coding. You can get a web site today that is "FREE", but you can also get one that cost many thousands of dollars. I try to describe what makes up a web site and where the money goes when developing and running a site.
I always appreciate feedback on these articles. If you have comments, questions, or suggestions please send them to support@mmcctech.com .
INDEX
THE PIECES OF THE WEB
COMPONENTS ON YOUR COMPUTER
The Web Browser:
As a user, you see the web from your computer's WEB BROWSER screen. The browser is just a software program that you run on your computer. A few years ago almost everyone would have been using Netscape. Today almost everyone uses Microsoft's Internet Explorer.
E-mail is one of the most popular features of the internet. Your e-mail program is usually separate from your browser. Today most people use Microsoft's Outlook "Express". Business users sometimes use the more comprehensive Outlook. There are a number of other e-mail email programs, including "browser based" e-mail which will be discussed below.
The Internet Connection
Your web browser and e-mail program connect to the internet using other software that runs on your computer. Unless you are on a dial-up service, you never really see that software because it works under the covers. If you are on dial-up you see this software only when it dials to make the connection.
That behind-the-scenes software is not part of your browser. Once you're connected, any program on your computer can use it to reach the internet. People who use high speed (broad band) connections, like DSL lines or Cable Modems, are always connected to the internet even if they are not using their browser.
Spyware, Viruses and Worms:
Everyone has heard of the feared computer virus and worm. A related creature is a controversial type of software called Spyware. These are all a type of software that is installed on your computer without your knowledge. Viruses and worms are often malicious and can cause significant grief. Spyware is more benign in that it doesn't do harm, but it can be an invasion of your privacy.
This entire class of programs takes advantage of the fact that, once you are connected to the web, any program can use that connection. These programs are built to automatically load when you turn on your computer and then they run in the background where you can't see them. Viruses aim to do harm to your computer. Worms often use your computer to reach out to other systems. Spyware watches you, collects information, and reports back to it's master.
These programs typically can't infect your computer on their own. You have to do something yourself to become infected. But that something is as simple as clicking a link in an e-mail. In the case of spyware, you often get it when installing a program. Even Windows has been accused of collecting information and reporting that back to Microsoft over the internet.
(It's worth noting that viruses and spyware are largely denisons of the Microsoft Windows world. Apple Macintosh and Linux users are largely immune. Even on Windows, people who use non-Microsoft browsers and e-mail programs have much less exposure than those using "IE" and Outlook. Viruses typically exploit the many holes in Windows and the easily accessible Outlook address book to do their damage.)
IN THE MIDDLE
Internet Service Providers (ISPs) are the companies which link your computer to the world. The internet itself is a huge infrastructure much like the phone system. In many areas the internet and the phone system in fact overlap and interconnect. At the heart of the network is the "backbone", which is the high speed service that connects everything together.
For you to use the internet you, or your employer, must pay for a connection to the backbone. In most cases the connection is "rented" from an ISP. The ISP pays for the direct, ultra high speed, connection to the backbone and then provides other methods for you to connect to their computer which routes you onto the backbone. The common anology is that the backbone is the "information super highway" and the ISP's are the "on-ramps". (Large businesses may act as their own ISP and purchase a dedicated connection straight to the internet backbone. This is relatively expensive proposition.)
In recent years the choices of connection have grown significantly. In general, these connections are classed as low-speed / dial-up and high speed or broadband.
Dial-up connections get that name because they use the standard phone system to connect your computer to a service provider. Your computer uses a standard telephone line and a device called a "modem" to dial up the service provider and then connumicate over that line. You can pick up a telephone and call that same phone number and you'd hear the service provider's computer answer with a high pitched tone. If you could whistle fast enough, you could even talk back to that computer.
Once the dial-up connection is made, your computer "talks" to the computer at the service provider. The service provider is connected to the internet with a high speed service and it just relays your computer's request out to the internet.
Broadband connections are typically a full time, dedicated connection between your computer and your service provider. The phone company provides a "Digital Subscriber Line" (DSL) service that may in fact use a dial up connection which might also carry your phone service. Cable television providers have become a major service provider by providing internet connections that share their TV cables.
The hot topic at the time of this writing is wireless connections. Medium speed wireless connections are becoming common within businesses. Public connections, sometimes called hot spots, are similar systems which are open to the public. On the high speed side a number of companies are providing rooftop dishes which communicate with the provider via radio towers.
At the high end of the connection options is the direct line to the internet backbone. There are several levels, but most people just call this a "T1" connection. These are very high speed connections and you are effectively your own service provider because you go directly to the backbone.
The Backbone is the heart of the internet. This is a network of very high speed, world wide cables and other connections which make up the real internet. This network is highly redundent and linked in a complex web of main trunks, branches and sub-branches.
The system that makes up the internet was designed during the cold war specifically to be self repairing. If a hub, or a link, or a cable is taken out of service (like bombed off the face of the earth), the network will automatically find another route to get messages through. In actual fact, the e-mail that you send to your next door neighbor could actually flash all over the world before arriving next door. The net just finds the best route it can and gets the job done.
The internet today is truly a world-wide network. There's hardly a place on earth (or even in earth orbit) which cannot reach the internet.
THE "IP" ADDRESS
Every device connected to the internet must have an Internet Protocol (IP) address. This is a special number, much like a phone number, which let's devices find and communicate with each other. There are two types of IP addresses:
Static IP addresses are dedicated to one piece of equipment and they never change. This is usually a more expensive connection service since the number of IP addresses has a limit.
Dynamic IP addresses are temporary addresses assigned using something called "DHCP" (dynamic host configuration protocol). In this case, a computer, or router, or other device takes a single, static IP address and sub-divides it for other computers.
A simple DHCP can run in your house. You get a single internet connection from your ISP and put connect a DHCP "server" (router, switch, computer, etc.) to that line. Each of the computers in your house are connected to the DHCP server. When you turn your computer on, the operating system goes to the DHCP server and requests a dynamic (temporary) IP address. The DHCP server pools messages and request from all the computers on your network and sends them out to the internet under it's own IP address. When data comes back, the DHCP server sends it to the proper machine using the dynamic address it assigned.
Dynamic connections are less expensive because the ISP can take a limited number of static IP addresses assigned to it and sub-divide them among many customers.
(DHCP hosts can be connected to other DHCP hosts. This allows tremendous branching and splitting using any number of otherwise duplicate IP addresses.)
Some internet functions require static IP addresses. A web site, for exmaple, must have a static address if it's going to be available for anyone to visit. If you tried to use a dynamic address, which can change every time you reboot the computer, your web site would disappear each time and re-emerge under a new address.
See DNS servers in the special systems section below.
WEB SERVERS
A Web Server is a computer connected to the internet that is running special software which can accept requests for information from outside and send (serve) that information back to the requester. These machines are the real work horses of the web.
In the simplest case, a web server is just a computer with data files stored on it's hard disk and a program which just monitors the internet. When a request comes in, the server software finds the requested data file and sends it back to the computer (person) who wants it. The server immediately forgets that person even exists and it waits for another request.
In the real world, of course, the web server is far more complex and does many, many more things.
E-mail servers are another program that runs on the web server computer. This software sets up disk files for registered users and calls them "post office boxes". E-mail directed to a person's e-mail address is routed to the appropiate e-mail server where it is processed and stored in the person's private P.O. Box (disk file).
Later the registered user contacts the same e-mail server with a password controlled login request. The e-mail server sends back a list of waiting messages. The user clicks on the message he wants and the server sends them to his machine over the internet. In most cases the server is set to then delete the messages from the P.O. Box file.
File Transfer Protocol (ftp) processing provides a method of transfering large amounts of data efficiently. Although this is sometimes done from your web browser, it's more common to use a program that is built just for FTP work.
An FTP "client" (the program that runs on your machine) will typically provide you with a method of logging onto an FTP server using a password. Once you're logged in, your FTP client will show you the folders and files on your computer in one screen, and the folders and files on the server in another screen. You can click on files and have then transfered in either direction.
Server Side Processing is a specialized type of program which can do just about anything on the web server itself. Many modern web sites, and all automated sites, use some form of server side processing.
In most cases where web sites are concerned, the only thing that happens is that your web broswer requests a web data file from the server. The server just grabs the requested file, ships it to your browser, then forgets you.
For more complex information, your broswer may be instructed to ask the server to run a program which will develop data that is to be sent back to you. The net result is about the same. The server gets your request. It sees that you want a program to be run rather than just a file retrieved. The server starts that program then goes back to other things. When the requested program is done, it prepares its response and calls the server to send the data back to you. As far as your browser is concerned, it just sent a request for a file and it got it back.
Server side processing can be very complex. Web programmers write software to do whatever their client needs. They often create and maintain database system on the web server. They have to build security systems, data validation, queries, update programs and so much more. This can be tedious, technical work, but it greatly expands the things that can be done on the web.
SPECIAL SYSTEMS
There are a number of special components of the internet. Most of these are built into the infrastructure and are seen only the by technicians who keep the net running. Components like routers and switches are scattered all over the web as well as in user offices. These and other systems keep messages flowing and the net functioning.
Domain Name Servers (DNS) are a special class of back room components that are important to making the "world wide web" work. Internally, every device on the internet is given a unique, numeric "Internet Protocol" (IP) address. It's much like a phone number. The IP address of the web site you're reading this on is "24.247.27.20".
Even though the world seems to do just fine using numeric phone numbers, the "world wide web" took a different tack by using an alpha-numeric "universal resource locator" (URL), the familiar "www" address. Domain Name Servers are machines which run the "phone book". Rather than typing in "24.247.27.20" to reach this web site, you can type in "http://www.mmcctech.com".
WEB SITES AND THE WORLD WIDE WEB
WHAT IS A WEB SITE
A web site is little more than a collection of computer files that are stored on a web server somewhere on the internet. The server that contains the web site files is called a "HOST". Many web sites can be hosted on the same server.
When you decide that you want a web site, building a simple site is a simple proccess.
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When you decide you want a web site, the first step is to find a place to have your site "hosted". You need a computer connected to the internet with a static IP address. There are thousands of companies which provide this service.
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With your host identified, you can "resigter" your web site name. That involves paying a fee, filling out some information, and having the name (www.MyTeddyBears.com) linked to the host web server. (Get some help with this so you don't make a false start.)
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Now that you have a host and a URL, you can begin to develop the web pages. For a simple web site, web pages are little more than text documents which contain some special "tags". You can type web pages in a word precessor (although there are better ways to do it), and you can do it on your own computer without even being connected to the web.
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The last step is to "upload" your web pages to the server and test them. Once your site is registered and you have stored some web pages there, the entire world can view your work.
We'll now review those steps in more detail. Again thinking in terms of a simple web site.
Finding a Web Host:
When you decide you want your own web site, the first step should be to find a host computer. This is a computer connected to the web using a static IP address. That computer must also run special "web server" software which monitors the internet for requests for information from your site and then sends or "serves" the requested files back. If you want to provide e-mail, FTP and other services, that's additional software.
If you have a static IP address on your Windows computer you could, in theory, host your own web site from your machine. In reality, the configuration and maintenace of the server software is more than most people want to do. It can also be expensive. The software components are not cheap. The truth is, even professional web site developers usually buy hosting from companies which specialized in that service.
Web hosting services charge a fee for storage, speed, software features, and other items. Professional web developers often buy hosting services in "bulk" then sub-divide this among many web site clients. It's not unusual for a web developer to buy hosting from several hosting companies, each with a different mix of services and costs.
Registering your web site name
The second step is to register your domain name (or "URL"). You want to call your site something like www.MyTeddyBears.com. Registering the name reserves that URL for you and tells the DNS name servers how to find you.
The reason registering the name should be the SECOND step is simple: In the early days of the web, there was a single, quasi-govermental, body responsible for registering all URL's. The web has since been "de-regulated" and a number of companies provide "registrar" services. Everybody's trying to sell stuff and it's not always clear what you're buying.
Registrars charge a fee to register your URL. Today it's around $75 for two years. When a URL is registered, it is linked to the IP address of the computer which will host the site. If you register your URL before you know the host computer, your site will probably be assigned to a host company alligned with the registrar. If you later find your own host, it can be painful to get the site re-linked.
Your FREE web site
For very simple web sites there are actually free services. Most ISP's provide limited web hosting as part of your internet account. The site is usually VERY limited, but it's there and can be fun to play with.
Besides your ISP, there are numerous web companies which offer some type free web site. Usually these are "virtual" sites which are really just another page on the company's own web site. Many times they're supported by advertising. Banner ads are sold based on the number of "impressions" or "views". Handing out small, free web sites may give a company thousands of new pages without any work. Each of these pages can show a banner ad which generates a fraction of a penny in revenue. Those "views" add up to some serious money. Unfortunately, you don't get any of it; you go the "free" web site.
HOW DOES A WEB SITE WORK
A software partnership
Making a web site work requires three software partners:
- The web server stores the web site files and sends them out as requested.
- The web pages are text documents which contain instructions for what the page is supposed to look like.
- The browser runs you your computer and is responsible for understanding the instructions and putting the page on your screen.
The Web Server
With some exceptions, the job of the web server is limited. It sits and waits for an information request from the outside world. When it gets the request, it finds the appropriate information and sends it back to whoever asked for it. The server does little more.
In special cases the web server will be instructed by the visitor to run some special software program. The server fires off that program as another task on the computer then goes back to waiting. When the separate software finishes its work, it passes the results back to the server which passes it on to the visitor.
Web Pages
are simply text documents. They are entirely readable by a person, although they contain some special text which may not make immediate sense. The special text, called "tags", instructs the web browser about how to display the text.
More will be said later about web pages, and the HTML "language" in which they are written.
The Web Browser is a piece of software you run on your computer. This is the real workhorse of the web experience. The browser is responsible for reading the HTML web page and following the enclosed instructions for putting the information on your screen.
In the early days of the web (the mid-1990's), there were several emerging web browser programs.
The first truly popular browser was Netscape, which became the standard by which all other browsers were measured. Once the internet took hold and the stock market "tech bubble" took off, Microsoft jumped in with both feet and put it's Internet Explorer (IE) on the front of Windows on every new computer. Today IE is the predominant browser and Netscape runs a poor second. There are several other browsers, such as Opera, but they have a small following.
The challenge for a web site developer is to write web pages which will run on any browser. The HTML language is a loose standard with no enforced compliance. As new browser versions emerged, each added features which were not necessarily part of the "standard". A feature which worked on one browser might not work on another.
As Microsoft IE became the predominant browser, most web developers began to write specifically for that browser. There are features that work on IE but will not work on other browsers. It's a trade off that developers accept.
Much like browser versions, another factor in web site development is something called Server Side Features. As mentioned before, the web server doesn't have much to do. It simply takes requests for data, finds the files, and passes them back to the visitor's browser. But the web browser can ask for more than just data. It can ask the server to run some special piece of software which will prepare data and return it rather than a data file.
Server side features (also called extensions) are the special programs that can run on the server. A very popular web development system is Microsoft's "Front Page". That system is like a desktop publisher, or word processor, designed just for web pages.
Today
pre coded
- stateless connecction and cookies
- html
- resources (pictures)
- frontpage, dreamweaver, composer
- java / javascript
- automation: cfm, asp, etc.
- databases
- e-mail servers and post office boxes.
- browser based e-mail
- e-mail scripts
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HTML: THE LANGUAGE OF THE WEB
Everything you see on the web is actually written in HTML or "HYPERTEXT MARKUP LANGUAGE" . HTML is an international standard defining a method for writing computer documents which are displayed in a graphical environment. HTML is used primarily for web pages but it can be, and is, used for many similar tasks. Although HTML is considered to be an "international standard", it's very young and it's evolving very rapidly. Keeping up can be a full time job.
(If you haven't looked at any HTML you should. Most web browsers have an option to view "document source". See if you can find that option to look at this simple page.)
HTML does not target specific machines, browsers or operating systems. Instead, it a general specification telling how to accomplish the goal of publishing documents. HTML does not itself display the pages you see on the web. Instead, your web BROWSER is responsible for interpreting the HTML code and presenting the content on your personal screen. Different browsers may produce different results with the same page.
WHAT DEVELOPERS CANNOT CONTROL
Because HTML doesn't control the final presentation of a page and because broswers are not completely consistent, web page designers can't be sure how their page will look to everyone.
"FONTS" are the source of quite a few problems. By "font" we mean the design and size of the letters that you see on the screen. Web page designers have Web page designers have a number of HTML tools to define what you're going to see but in most cases, little more is done than to indicate a relative size and, maybe, a color. YOU are responsible for setting a base font size in your browser. The final fonts that you see are displayed in relation to your default font and size.
If you haven't tried it, look through your browser's options and see if you can find the FONT specification. You can change the size and typeface and other things and this very page will change to match.
Because you control the final look of the text in a web page, some designers will actually send "pictures" of words rather than actual text. They'll use a drawing or painting program to make cool looking text and then send the image rather than just text. That's great but it's also slower.
Some people have problems with how images are positioned on the screen. They'll look at a web page and find that images run off the edge of the screen or they're fuzzy or they cause the text to be pushed off of the screen.
Most of these problems show up with Microsoft Windows systems. Often they're caused by the screen resolution which Windows allows you to control. The most common resolution is 640 x 480 pixels which produces relatively large and easy to read images. More experienced users prefer 800 x 600 which produces smaller images and get's more information onto the screen. (A few eagle eyed people can read 1024x768 and higher.)
In our case we use the medium 800 x 600 resolution. The pages we design fit well at that resolution but may run over the edge of the screen when viewed at a lower resolution.
WHO CONTROLS THE SPEED?
Probably the loudest complaint people have concerns SPEED. Everyone gets frustrated when a page just seems to sit there and do nothing for ten minutes.
There are many factors affecting the speed you experience. SOME factors cannot be influenced by the web page designer. We can't alter the speed of your local connection, the number of users on the web itself, the number of users accessing the specific site you're looking at and, of course, problems that can occur anywhere in the world wide network. That's just the way the net works.
There are MANY things that the developer CAN control. In particular, using fewer and smaller images really helps. Writing lots of small pages is often better than a few large ones. Limiting animation, splashy graphics and heavy use of "scripts" can help. Basically, anything that reduces the amount of data that must be sent down the wire helps improve speed.
WHAT DESIGNERS SHOULD DO
All web page designers have a responsibility to the internet community. There are common sense things we can to make our pages work well for everyone. At MMCC we make a point of making our pages as efficient as possible. We call this our WEB-SPEED policy.
The most important thing a designer can do is to test his pages in more than one browser environment. At MMCC we work from three offices, each with different web tools and browsers. We subscribe to America-On-Line, CompuServe and Concentric Network (a general internet service provider). We test our pages on all of these services with Netscape, Microsoft Explorer and AOL's browser. If things work in all of those environments we figure we're fairly safe.
WHAT YOU CAN DO
If you're having problems you may want to check your browser options. You can usually control screen resolution, base fonts and colors. Depending on your browser you may have other options as well. The real key to happy browsing is to educate yourself and learn what your options are.
WHAT PEOPLE COMPLAIN ABOUT
A few things seem to be on everyone's mind. We hear them over and over when we talk about web pages. The most consistant complaint is "IT'S TOO SLOW!". Everyone gets frustrated when a page takes forever to load.
Other common complaints deal with bad colors, fonts that are too large or too small and pages which run off the screen or don't seem to display in a logical fashion.
Many of the problems are design related (and should be corrected). Pages overloaded with huge pictures are always going to be slow. Blue letters on a black background must have been designed by aliens because normal human beings find them nearly impossible to read. Designers who insist on using every new gizzmo make pages that won't work with every browser.
But not all problems are the page designer's fault. Some problems are on the browser's side.
They're things that you can control. To understand those things it helps to know a bit about HTML.
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