Graphics á la the Web

Sending text over the Internet is just old fashioned e-mail. When you can include Pictures, your message can be much more informative!

Objectives

After this lesson, you will be able to:

Identify the graphic format for the World Wide Web.
Discuss key points to consider when including graphics in WWW documents.
Download a graphic file to your computer.
Use the correct HTML format for including pictures in your WWW document.

Lesson

The WWW's Graphic Format

There are many different file formats for computer graphics. The way a WWW browser works is that HTML codes indicate the location of a graphic file in a format that can be interpreted by different types of computers. When the information in that format is received by a Macintosh computer, a WWW browser knows to display it as a PICT format. However, when that same information is received by the Windows version of the same WWW browser, it is displayed as a Windows BMP format.

The major graphic format that a WWW page can display within a document is GIF or Graphics Interchange Format . A GIF image compresses the picture information (reduces the file size) and exists in binary code that can be sent over the Internet.

Several graphics programs have built in features to save files as GIF format. If not, there are several shareware programs for performing the conversion, listed with links to Internet archives where you should find these applications:

Macintosh: "GIFConverter"
University of Texas * Merit Archives * Info-Mac Mirror Archive
Windows: "WinGif 1.4" or "lview 3.1"
Merit Archive * Oak.oakland.edu * wuarchive.wustl.edu * archive.orst.edu

Points to Consider When Using Graphics

For this lesson, you do not have to use one of these graphics programs. However, as you begin to develop your own WWW lessons, you should become familiar with creating pictures in either GIF format. If your WWW documents include graphics, keep these points in mind:

Large and numerous images may look great on a high end computer, but they will frustrate users who must wait for images to be sent over the network. As a suggestion, keep images less than 150k in file size.
Rather then displaying all of the images on the WWW page, have them linked as external images that are downloaded only when a user clicks on a hypertext item (this will be covered later in lesson 8d).
A single image can appear several times in a WWW document with little added delay each time you use that same image.
Most importantly, make sure that the images are ones that add meaning to your WWW documents.

Saving and Including Pictures in Your WWW Document

For the next lesson you will first need to download a copy of a GIF image. Follow these steps to save and include a snazzy picture of HOT lava that will be used to introduce your WWW document:

Go to the WWW browser window containing this page.
If you are unfamiliar with saving graphics files to your hard drive, see this list of instructions.
The picture below is a reduced copy of the image. Click on it once to download the GIF file to your computer.
Save it in the same directory as your HTML text file as file name: lava.gif

Check Your Work

Check to see that the file, "lava.gif", is saved in the same directory/folder as your HTML text file, "Volc.html". If it is not there, check to see if you accidently saved it in another directory/folder. Then, move it to the correct location.

Review Topics

What is the major graphic format for the World Wide Web?
How does this graphic format work to send pictures over the Internet?
What are some key points to consider when including graphics in WWW documents?
How did you save the lava graphic for use in your WWW document?

Independent Practice

Use the World Wide Web to browse the Internet for pictures. Try to download at least one image that might be useful for your page.

Coming Next....

Write the HTML code to have the lava picture displayed in your document.

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Writing HTML Lesson 7: Graphics á la the Web

The Internet Connection at MCLI is Alan Levine--}
Comments to levine@maricopa.edu