In the beginning of this tutorial I made the comment that Web pages are nothing more than a simple text file. At that time you may have said to yourself "How can this be true? I see web pages with graphics and sounds all the time !" Well, it is true. All an HTML file does is tell a browser where to put images, and where to find them. In reality, images aren't even downloaded when you first get a web page. The HTML file is downloaded, read by the browser, then the browser makes a new connection to the Internet to retrieve each image mentioned. Image files are also a lot larger than simple HTML files, so pages with lots of images can take a long time to download and view.
I'm not going to get into ways to create images for web pages in this tutorial because there is a lot of personal preference involved. I will tell you that the Internet has two primary formats for images, GIF's and JPG's. GIF's are limited to 256 colors and are very good for most graphics used on web pages. JPG's can have more than 16 million colors and are good for photographs or other images where you need a fairly high resolution. Because of the type of compression used, JPG's are typically smaller files than GIFs, but due to the amount of information they contain will usually take longer to download and display. There are a lot of graphics programs available that you can use to create images for your web page, from simple paint programs to commercial photo manipulation programs. Basically any program that will save a file in GIF or JPG format can be used. All the images in this tutorial are GIFs.