Graphic File formats

The two commonly used graphic file formats are gif and jpg. These two formats are viewable in all browsers that support graphics. Other file formats (eg: bmp or png) may be viewable in some browsers, but not all.

Which format is best varies from image to image, depending on it's characteristics.

You can not change which format an image is just by changing its extension. You must convert it using a graphics program such as Fireworks.

GIF

Images can have a maximum of 256 colors in them.

Images can have transparent parts.

Images can be animated.

Images with large horizontal chunks of a single color can be very efficient as gifs.

Most of the drawings, icons, banners, and button images you see on the web are in gif format.

You may hear something about Compuserve owning the patent on gifs. This is true, but don't worry about it. Companies that make software that can make gifs, must pay Compuserve a license fee. Individual users of gifs or gif making software don't have to pay Compuserve for them.

JPG

Images can have millions of colors. So photographs or other images that are highly detailed or have 3-D effects look better as jpgs. The file size is also smaller for these types of images as jpgs.

Jpeg and jpg are the same thing.