Welcome to the Introduction to WWW/HTML online class notes. A very similar tutorial has been given to IBM Rochester, University of Minnesota and a few companies in the Mid West. Please note that this is the master copy and will be updated from time to time.
Basic understanding of why WWW exist
Basic understanding of what the players are (browsers, network protocol, web server, etc)
Basic coding of HTML and Why it works !
The "Name" of the PC - My Computer
The "Languages" of the PC can talk - Network Neigborhood
The "Phones" available on the PC - Your Web Browser
Computer that link together in a local area (Using ethenet, token ring)
Computer that talk the same language (NETBEUI in Microsoft Network, IPX in NetWare, TCP/IP in the Internet)
Computer talks the Internet Language - TCP/IP
- Using "Gateway" in a LAN environment,
- Company paid for it
- Company "Firewall" log the data
- Using Modem and Dial up Networking at Home
- Need a ISP (Internet Service Provider, e.g. AOL)
- Local call and ISP fee
- ISP administrator can look at it
A killer app that talks a very friendly network language (HTTP)
Easy access to information
Easy exchange of information
User friendly "phone" - your browsers
We need the network language (protocol) that enable one another to talk
We need another language that create document
As the information superhighway (Internet) glows exponentially over the years, customers of the superhighway demand a need for one tool, one program, one appli cation that will take it from being a much-hyped but difficult-to-use linking of com puters around the world to being a highly informative, highly usable database and communications tool. The spreadsheet was the killer app for PCs a long time ago, but so far the Net doesn't have one. Some have given a potential "killer app" status to a program called Mosaic, Netscape or Microsoft IE.
What the superhighway does have at this point is a killer concept called World Wide Web (WWW). The WWW provides the technology needed to offer a navigable, attractive interface for the Internet's vast sea of resources, in much the same way that the toolbar on a word processor screen obscures the intimidating codes that the program actually consists of. The most accurate terminology might be meta-interface-an interface that incorporates other interfaces. WWW is a concept, not a program, not a system, and not even a specific protocol. It is the concept that brings internet users together through different applications and interface to access infor mation from the internet.
Nowadays, advertisements and editorial content in many publications such as Newsweek, Time, The New York Time, and the Wall Street Journal now routinely use the Web's identifying scheme, the Universal Resource Locator, as a means for directing the user to further information. Small business, organizations, even US White House, and individuals all over the world also use the Web for communication, information, and interaction.
This intense interest in the Web is a result of the potential it offers for communication. Using the Web, individuals or organizations can instantaneously and continuously present hypermedia--text images, movies, and sound-to a GLOBAL audience. For Web developers, this information environment demands excellent, effective content development in order to rise above the information clutter. With so much information on the Web, only that which truly meets user needs well can survive and flourish.
HTML is a subset of the SGML, or Standard Generalized Markup Language. HTML is now the "standard" code used in the internet to make documents readable across a variety of platforms and software. HTML operates through a series of codes placed within an ASCII document. These codes are translated by a "World Wide Web Client" such as Mosaic, Netscape, OS2 WWW Explorer or MacWeb into specific kinds of formats to be displayed on the screen, and on which the user can act (for example, send a mail).
HTML is a glowing language, it stays around and more complex it is becoming. Please refer to the lastest documentation for update.
HTML documents are plain-text (also known as ASCII) files that
can be created using any text editor (e.g., Emacs or vi on UNIX
machines; BBEdit on a Macintosh; Notepad on a Windows machine).
You can also use word-processing software if you remember to save
your document as "text only with line breaks."
Some WYSIWYG editors are available (e.g., HotMetal, which is available for several platforms or Adobe PageMill for Macintoshes). You may wish to try one of them after you learn some of the basics of HTML tagging. It is useful to know enough HTML to code a document before you determine the usefulness of a WYSIWYG editor.
If you haven't already selected your software, refer to an online
listing of HTML editors (organized by platform) to help you
in your search for appropriate software.
If you have access to a Web server at school or work, contact
your webmaster (the individual who maintains the
server) to s ee how you can get your files on the Web. If you do
not have access to a server at work or school, check to see if
your community operates a FreeNet, a community-based
network that provides free access to the Internet. Lacking a
FreeNet, you may need to contact a local Internet provider that
will post your files on a server for a fee. (Check your local
newspaper for advertise ments or with your Chamber of Commerce
for the names of companies.)
An element is a fundamental component of the structure of a text document. Some examples of elements are heads, tables, paragraphs, and lists. Think of it this way: you use HTML tags to mark the elements of a file for your browser. Elements can contain plain text, other elements, or both.
To denote the various elements in an HTML document, you use tags. HTML tags consist of a left angle bracket (<), a tag name, and a right angle bracket (>). Tags are usually paired (e.g., <H1> and </H1>) to start and end the tag instruction. The end tag looks just like the start tag except a slash (/) precedes the text within the brackets.
Some elements may include an attribute, which is additional information that is included inside the start tag. For example, you can specify the alignment of images (top, middle, or bottom) by including the appropriate attribute with the image source HTML code.
NOTE: HTML is not case sensitive. <title> is equivalent to <TITLE> or <TiTlE>.
Not all tags are supported by all World Wide Web browsers. If
a browser does not support a tag, it (usually) just ignores it.
Every HTML document should contain certain standard HTML tags. Each document consists of head and body text. The head contains the title, and the body contains the actual text that is made up of paragraphs, lists, and other elements. Browsers expect specific information because they are programmed according to HTML and SGML specifications.
Required elements are shown in this sample bare-bones document:
<html> <head> <TITLE>A Simple HTML Example</TITLE> </head> <body> <H1>HTML is Easy To Learn</H1> <P>Welcome to the world of HTML. This is the first paragraph. While short it is still a paragraph!</P> <P>And this is the second paragraph.</P> </body> </html>
The required elements are the <html>, <head>, <title>, and <body> tags (and their corresponding end tags). Because you should include these tags in each file, you might want to create a template file with them. (Some browsers will format your HTML file correctly even if these tags are not included. But some browsers won't! So make sure to include them.)
Hyperlinks (Hypertext links) are why we can jump from one document to another
This is a absolute hyperlink
<a href="http://www.yahoo.com">Using a Search Engine</a>
This is a relative hyperlink
<a href="filename.htm">Linking to a local link</a>
Build the marker for the anchors, the <A> Tag:
<A NAME="MyPagePart"> Click Me </A>
A link to an external marker:
<A HREF="filename.html#MyPagePart">Jump to an External Anchor</A>
A link to an internal marker:
<A HREF="#MyPagePart"> Jump to an Internal Anchor</A>
The following link will
jump to the top of this page. At the top of the page, we define:
<h1 align="center"><a name="Top">Introduction to WWW/HTML</a></h1>
And the link above actually has
the coding of
Order List - Number will show up:
<OL> ... </OL>
Unorder List - Bulleted List
<UL> ... </UL>
The element within List
<DT>Term Name<DD> Term Definition
<DT>Term Name 2<DD> Term Definition 2
To see a copy of the file that your browser reads to generate the information in your current window, select View Source (or the equivalent) from the browser menu. The file contents, with all the HTML tags, are displayed in a new window.
This is an excellent way to see how HTML is used and to learn tips and constructs. Of course, the HTML might not be technically correct. Once you become familiar with HTML and check the many online and hard-copy references on the subject, you will learn to distinguish between "good" and "bad" HTML.
Remember that you can save a source file with the HTML codes and use it as a template for one of your Web pages or modify the format to suit your purposes.
With an valid userid, e.g. ibmjoeuser. Sign on as ibmjoeuser and do the following steps to create a homepage under IBM Rochester:
A list of files are available under "gump.watson.ibm.com(188.8.131.52)/pub/httpdos2/." The following is a sample list:
README 2 Kb Tue Apr 11 00:00:00 1995 code10.zip 452 Kb Tue Apr 11 00:00:00 1995 core 29 Kb Tue Oct 1 06:31:00 1996 misc/ Thu Jun 15 00:00:00 1995 Directory ncsadoc.zip 549 Kb Wed Mar 8 00:00:00 1995 patch10.zip 105 Kb Tue Apr 11 00:00:00 1995 src10.zip 91 Kb Tue Apr 11 00:00:00 1995 unzip.exe 90 Kb Fri Feb 17 00:00:00 1995
The following is the installation guide:
Quick Installation Guide 1. Copy the package file code10.zip to the root directory of your choice. HPFS drive is much preferred, but it will also work on a FAT drive. 2. You must use PKZIP 204g compatible decompression program. Do not use a DOS-mode archiver because HTTPD for OS/2 contains long file names. InfoUnzip for OS/2 works best. A copy of InfoUnzip for OS/2 can be found in the same place you found this package. 3. Unzip the package file with the -d switch so that the correct directory tree will be created. unzip -d code10.zip 4. CD to httpd, and start the server. httpd 5. Now start your favorite web browser, and off you go! 6. Optionally, you can install NCSA documentation online. Copy ncsadoc.zip to the same root directory and issue unzip -d ncsadoc.zip. When unzip asks if you want to replace an "index.html" file, reply yes. 7. If your document root is on a HPFS drive, you may want to turn "FATTranslation" off in conf\srm.cf. You can just comment out the line.
Note: After installation, your home page will
be in c:\httpd\www\index.html
Setting Up an HTTP Server On An AS/400
<HTML> <HEAD> <TITLE> Welcome to AS400 Home Page! </TITLE> </HEAD> <BODY> <H1 align=center>Hi.</H1> </BODY> </HTML>
Pass /* /QSYS.LIB/HTTP.LIB/HTDOCS.FILE/* AlwaysWelcome On AccessLog WWWAccess ErrorLog WWWError
Use of Personal Web Server for Testing (Download from Microsoft)
Use of an Editor
Use of Web Browser
(Put it up on the server)
ez2html: Converts datastream files into WWW documents What ez2html is Ez2html reads any datastream file (with styles and insets, created by EZ), or plain ASCII file, or source code, converts that input into HTML+ tag format, and outputs the result to stdout. "HTML+ tag format" is the markup used by documents on the World Wide Web. See the htmltext help for more details. Starting ez2html To convert a file to HTML+, invoke the following command: ez2html [-h] [-o dataobj] [infile] -h Displays usage help. -o dataobj Tells the converter which dataobject to use, in case the file extension is not mapped in /usr/andrew/lib/global.ezinit. See the ez-extensions help for more info. infile Name of file to read as input. If omitted, stdin will be used. Examples ez2html -o ctext <~/bin/myshell> ~/WWW/myshell.html
1.1 Why the BM Utilities? The DynaMIT project is a travel behaviour simulation written in C++, and intended to be built upon by the author and others to perform various experiments on travel behaviour. The framework must be maintainable and documentation is an essential part of that. 2.1 Invoking bmu 2.1.1 Command-Line Syntax You can invoke the bmu program with syntax like the following: bmu
fn<.ext> fn filename of master input file ext extension of master input file - default .scr Options: -f format select output format: can be html format for WWW HTML browsing - the default latex format for LaTeX processing -m mainfn specify main file - mainfn.toc will be used as toc input -od outdir specify output directory - default current directory
Using export functions from Word Processer (MS Word, Lotus Word Pro, etc)
Using export functions from presentation Tools
Web Editing Tools
Most Web browsers can display inline images (that is, images next to text) that are in X Bitmap (XBM), GIF, or JPEG format. Other image formats are being incorporated into Web browsers [e.g., the Portable Network Graphic (PNG) format]. Each image takes time to process and slows down the initial display of a document. Carefully select your images and the number of images in a document.
To include an inline image, enter:
where ImageName is the URL of the image file.
The syntax for <IMG SRC> URLs is identical
to that used in an anchor HREF. If the image file is
a GIF file, then the filename part of ImageName must
end with .gif. Filenames of X Bitmap images must end
with .xbm; JPEG image files must end with .jpg
or .jpeg; and Portable Network Graphic files must
end with .png.
You should include two other attributes on <IMG> tags to tell your browser the size of the images it is downloading with the text. The HEIGHT and WIDTH attributes let your browser set aside the appropriate space (in pixels) for the images as it downloads the rest of the file. (Get the pixel size from your image-processing software, such as Adobe Photoshop.)
For example, to include a self portrait image in a file along with the portrait's dimensions, enter:
<IMG SRC=SelfPortrait.gif HEIGHT=100 WIDTH=65>
NOTE: Some browsers use the HEIGHT
and WIDTH attributes to stretch or shrink an image
to fit into the allotted space when the image does not exactly
match the attribute numbers. Not all browser developers think
stretching/shrinking is a good idea. So don't plan on your
readers having access to this feature. Check your dimensions and
use the correct ones.
You have some flexibility when displaying images. You can have images separated from text and aligned to the left or right or centered. Or you can have an image aligned with text. Try several possibilities to see how your information looks best.
Aligning Text with an Image
By default the bottom of an image is aligned with the following text, as shown in this paragraph. You can align images to the top or center of a paragraph using the ALIGN= attributes TOP and CENTER.
This text is aligned with the top of the image (<IMG SRC = "5.hkbut.gif" ALIGN=TOP>). Notice how the browser aligns only one line and then jumps to the bottom of the image for the rest of the text.
And this text is centered on the image (<IMG SRC = "5.hkbut.gif" ALIGN=CENTER>). Again, only one line of text is centered; the rest is below the image.
Images without Text
To display an image without any associated text (e.g., your organization's logo), make it a separate paragraph. Use the paragraph ALIGN= attribute to center the image or adjust it to the right side of the window as shown below:
<p ALIGN=CENTER> <IMG SRC = "5.hkbut.gif"> </p>
which results in:
The image is centered; this paragraph starts below it and left justified.
Some World Wide Web browsers--primarily those that run on VT100 terminals--cannot display images. Some users turn off image loading even if their software can display images (especially if they are using a modem or have a slow connection). HTML provides a mechanism to tell readers what they are missing on your pages.
The ALT attribute lets you specify text to be displayed instead of an image. For example:
<IMG SRC="UpArrow.gif" ALT="Up">
where UpArrow.gif is the picture of an upward pointing arrow. With graphics-capable viewers that have image-loading turned on, you see the up arrow graphic. With a VT100 browser or if image-loading is turned off, the word Up is shown in your window.
You should try to include alternate text for each image you
use in your document, which is a courtesy for your readers.
Newer versions of Web browsers can load an image and use it as a background when displaying a page. Some people like background images and some don't. In general, if you want to include a background, make sure your text can be read easily when displayed on top of the image.
Background images can be a texture (linen finished paper, for example) or an image of an object (a logo possibly). You create the background image as you do any image.
However you only have to create a small piece of the image. Using a feature called tiling, a browser takes the image and repeats it across and down to fill your browser window. In sum you generate one image, and the browser replicates it enough times to fill your window. This action is automatic when you use the background tag shown below.
The tag to include a background image is included in the <BODY> statement as an attribute:
By default browsers display text in black on a gray background. However, you can change both elements if you want. Some HTML authors select a background color and coordinate it with a change in the color of the text.
Always preview changes like this to make sure your pages are readable. (For example, many people find red text on a black background difficult to read!)
You change the color of text, links, visited links, and active links using attributes of the <BODY> tag. For example, enter:
<BODY BGCOLOR="#000000" TEXT="#FFFFFF" LINK="#9690CC">
This creates a window with a black background (BGCOLOR), white text (TEXT), and silvery hyperlinks (LINK).
The six-digit number and letter combinations represent colors by giving their RGB (red, green, blue) value. The six digits are actually three two-digit numbers in sequence, representing the amount of red, green, or blue as a hexadecimal value in the range 00-FF. For example, 000000 is black (no color at all), FF0000 is bright red, and FFFFFF is white (fully saturated with all three colors). These number and letter combinations are cryptic. Fortunately an online resource is available to help you track down the combinations that map to specific colors:
You may want to have an image open as a separate document when a user activates a link on either a word or a smaller, inline version of the image included in your document. This is called an external image, and it is useful if you do not wish to slow down the loading of the main document with large inline images.
To include a reference to an external image, enter:
<A HREF="MyImage.gif">link anchor</A>
You can also use a smaller image as a link to a larger image. Enter:
<A HREF="LargerImage.gif"><IMG SRC="SmallImage.gif"></A>
The reader sees the SmallImage.gif image and clicks on it to open the LargerImage.gif file.
Use the same syntax for links to external animations and sounds. The only difference is the file extension of the linked file. For example,
<A HREF="AdamsRib.mov">link anchor</A>
specifies a link to a QuickTime movie. Some common file types and their extensions are:
|X Bitmap image||.xbm|
|JPEG image||.jpg or .jpeg|
|AIFF sound file||.aiff|
|AU sound file||.au|
|WAV sound file||.wav|
|MPEG movie||.mpeg or .mpg|
Keep in mind your intended audience and their access to
software. Most UNIX workstations, for instance, cannot view
Create a Web Page just like the following picture:
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