Lecture notes

250.02 -
Web Design

World Wide Web

The Internet
Universality
HTML

HTML & Info Path

Web authoring
Servers
Modems
Browsers
URLs

Creating a site

Organizing Files
Design Issues
Dynamic HTML
Plugins

Managing a site

UBArt server (LAN)
UB UNIX (FTP)

HTML and the Information Path

Web Authoring Some Web authors use text programs such as Microsoft Word or BBEdit to write HTML code directly, while most use graphical programs like Adobe GoLive or Macromedia Dreamweaver. Graphical, WYSIWYG (what-you-see-is-what-you-get) programs automatically write HTML code from the designers visual layout. Whatever type of HTML authoring program is used, HTML documents are always saved as text documents which can be read on any platform by any text editing program.

Servers Once an HTML document is created it is transferred to a computer known as a server. A server's sole purpose is to send Web pages to user's browsers when requested. Servers are usually located at large educational institutions, businesses, laboratories, or Internet Service Providers (ISPs), though personal Web servers are becoming more popular.

Modems To access an HTML page user's computers have to call out to a server. Users have traditionally used special computer telephones, or modems, to make these connections. Phone lines are becoming increasingly too slow as Web content becomes more complex and Internet traffic increases. Modem speeds (28.8 kbps to 56 kbps) have relatively low bandwidth and the transfer of a single Web page can take from a couple of seconds to a minute or more. To help alleviate the problem of old phone lines, new digital lines are being installed and used by many universities, large companies and private households. These ISDN, DSL (typically around 1000 kbps), cable modem and T1 technologies speed Internet access by a factor of 10 to 100.

Browsers Once a computer is connected to the Internet it needs a program, called a browser, which will interpret HTML code as it is downloaded. Browsers interpret HTML code and render page layouts.

Browsers are evolving just as rapidly as HTML and the Web itself. The two most popular browsers are Netscape Navigator (Communicator) and Microsoft Internet Explorer. These two browsers are free. The problem with these two browsers is that they don’t always interpret HTML code in the same way, or support Web standards consistently. This means that a page may look as the designer intended in one browser and look very different in another.

URLs — Uniform Resource Locators are addresses of computers and documents available to access on the Internet. A URL usually consists of the connection protocol (such as http://), the name of the host computer (either an IP address, such as 128.205.120.196 or a Domain Name, such as www.art.buffalo.edu) and the specific document location within the folders of the host computer (such as /workshops/paths.html).

Together, the example given would appear as <http://www.art.buffalo.edu/workshops/paths.html>. Clicking on a link to the "paths" page would tell your browser to call out to the computer named "www.art.buffalo.edu", look into the "workshops" folder, and get the page named "paths.html".