| In my experience teaching Dreamweaver, I've found that some people new to Web design don't understand how graphics used in Dreamweaver were created. It's important to understand that Dreamweaver has no image-editing capabilities as a standalone application. Dreamweaver integrates well with some image editing programs such as Fireworks and Photoshop, but you cannot create or edit graphics inside of Dreamweaver. Dreamweaver is strictly the application for laying out content in an HTML form. Therefore, let's briefly discuss what image formats are acceptable for the Web. GIFs GIF stands for Graphical Interchange Format and is used for images or graphics with smaller amounts of color and graphics without much tonal range. The reason is that because GIFs read color in a horizontal line, the more color it encounters when reading, the larger the file size. GIFs also have a color table attached to them. The color table dictates to the graphic how many colors and which color can be used in the artwork. More colors in the color table yield higher file sizes. GIFs can also store transparency; for example, if you have an image with a solid background color, yet you didn't want to see that background, you can make it transparent. Creating GIFs with transparency requires you to master a few tricks, but that topic is out of the scope of this book. If you're new to creating content for the Web, I suggest visiting Web sites such as www.Webmonkey.com. GIFs create the smallest file sizes and are best used for flat, lower-colored graphics. JPEGs JPEG stands for Joint Photographic Experts Group and is a lossy compression standard used on bitmap graphics with great tonal range, such as photographs. This compression standard removes pixels from an image to reduce the file size. Too much compression can result in a blurry, unclear image. If you're moving over from the print world, the notion of removing pixels may seem like a sin. Remember that people will be viewing the artwork on a computer monitor, and it isn't intended to be viewed in any other format. If the image looks good on a monitor, that's all you need to be concerned with. Many of the image-editing applications have great features for compressing bitmaps. PNGs PNG stands for Portable Network Graphics, and a big buzz was associated with them a year or two ago. They were supposed to replace GIFs for a number of reasons, but the main one was the capability for PNG to be saved in many bit-depths. GIFs are limited to a bit-depth of 8, whereas PNGs can be saved from anywhere between 8-bit to 32-bit color. They never really caught on. Maybe they will in the future, but if you decide to use them, be aware that only Internet Explorer 4 and later can view them. | 
