To create an animated GIF, one simply makes a series of images(called frames) that are played by the web browser one by one at a speed that fools the eye into thinking that it is one image that is moving. It is the same technology used by Hollywood movies as well as video tape producers. This technology relies on the fact that human eyes have limitations. Whenever your eye sees an image and the image is removed, there is a small delayed image(afterimage) that your brain still sees. A number of factors determine the length of the afterimage including intensity of the image, colors, and especially the medium that that image is shown on. For motion pictures to "fool" your eyes and brain, a filmmaker needs to create 24 individual images in one second so that the movement appears smooth to your eye. Video technology requires 30 frames per second to smooth the animation out.
As far as computers and monitors are concerned, there is good news and bad news. The bad news is that even the today's fast CPU's(computer processors) and video cards cannot run frames as fast as a movie projector or video player. 
Animations on webpages still are not as smooth as movies or video. The good news is that you as the creator do not need to create so many darn frames!! About 12 frames per second is all you need to maximize the smoothness of a standard desktop computer. The little animation to the right(perhaps the dumbest ever made) is 10 frames. Time it to see how long it takes to cycle through those 10 frames on your computer. The animation continues to "loop"(repeat itself) so time it through one cycle. Depending on your CPU and your video card, it should take a little less than a second(10 is a little less than 12). Notice that the animation is less than smooth but not overly jerky.
Photoshop 5.5(or even 4.0 for that matter) works fine for creating the individual frames for an animation. What you then need is a type of software that can compress these individual files into an animated GIF. There are several applications that you can download at home if you do not have Photoshop 5.5 with Image Ready. Since we have Image Ready here, we will use it as our animation compresser. It also is a fine tool for creating the individual frames. That is what we are going to use in this class. Just makes it simpler. However, if you find(or create) a series of images that you would like to compress into an animated GIF, you can import them into Image Ready. Make sure the images are in the correct order(i.e. 01.gif, 02.gif, 03.gif, etc.) and in a folder. Then go File...Import...Folder as Frames. For our purposes, we will show you 2 skills:
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