Whether .GIF or JPEG, it's all about pixels, color, and compression. Even if you're a beginning World Wide Web publisher, you are sure to discover lots of good reasons to include various kinds of images in your online documents. On the most basic level, pictures give your Web pages more visual appeal. As you compete for readers' attention, images are often a good way to entice and encourage visits to your Web site.
Pictures can also serve an informational purpose.
Remember that it is the World Wide Web. Diagrams, photographs, maps, and picture icons can help convey your message to international Web surfers who may not be fluent in English. You can even use pictures of text to overcome design limitations of Web publishing, specifically HTML codes. You can designate the hierarchical relationship between elements by designating which text string is a first-level headline and which paragraphs are body copy, but you can't specify typeface or point size. As the publisher, you can guarantee that a particular type style will appear on your Web pages only by generating a picture of the text and inserting it into your HTML documents as a graphic.