Building a transparent GIF

When you put an image on your web page, you have to consider that your image has a foreground color and a background color. Besides ANY image is a rectangle or a square. So what if you want to build a little circular button? Well, you have to 'hide' its background color! In other words you have to build a transparent background. Look a simple GIF WITHOUT a transparent background:

As you can see, there is an ugly gray background...Now take a look at the same GIF WITH a transparent background:

Do you got the idea? Ok, now you are wondering: how can I do that? Simple: your favorite graphics program can do that job. If you use PaintShop Pro 5:

Click on 'Colors'
Click on 'Set Palette Transparency'
Choose 'Set the transparency value to the current background color'

Or press 'Ctrl-Shift-V'. If you are using Photoshop 5:

Create a new file choosing 'RGB' and 'transparent'
Click on 'Export' then 'Export GIF89a'