Can background color be invisible?

I made a circle with graphics and I need the background color to be transparent or better yet I only need the circle without the background. I've made the graphic to use on swish but it comes over with the pixel size that the circle was made with (400x400). Now I am unable to use other colors other than what the background is on swish.

Thank you in advance for your assistance.

Make sure the transparent area is transparent and do File|Save As. Select .Gif and press Ok. Be sure to check the Transparency box too after you hit Ok.

I'll try that, thanks.