Animation is the final advantage offered by the GIF89a format. Certain software programs enable you to
group your GIF files together into one large page-flipping file. With this capability, you can bring simple
animation to your page without additional plugins or helper applications. Unfortunately, the trade-off is that
the files get very big, very fast. For more information about animated GIFs in Dreamweaver, see the section
???Applying Simple Web Animation??? later in this chapter.
JPEG
The JPEG format was developed by the Joint Photographic Experts Group specifically to handle photographic
images. JPEGs offer millions of colors at 24 bits of color information available per pixel, as opposed
to the GIF format??™s 256 colors and 8 bits. To make JPEGs usable, the large amount of color information
must be compressed, which is accomplished by removing what the compression algorithm considers
redundant information.
JPEG files can be named with a file extension of .jpg, .jpeg, or .jpe. However, the most
commonly used extension is .jpg.
The more compressed your JPEG file, the more degraded the image. When you first save a JPEG image,
your graphics program asks you for the desired level of compression. For example, consider the three
images shown in Figure 9-2 and compare the effects of JPEG compression ratios and resulting file sizes to
the original image itself.
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