JPEG is the standard of choice because of its high resolution and high compression. Many graphic editors, such as Corel Photopaint, let you choose a quality setting for the compression. In addition JPEG supports 24-bit color, GIF only 256 colors. Unlike GIF, JPEG unfortunately doesn't support animated, transparent or interlaced images. GIF89a includes a transparency index that causes the background color of the display to remain unchanged for the color indexed as transparent .
Interlaced images means the image can be progressively displayed.
When an interlaced file is downloaded, it appears with a venetian blind effect. Interlaced images let the user begin viewing the rest of the document while the image is downloading. Adding images to your web pages can give them a polished, professional look. One of the biggest hurdle in creating you own web page, however, is acquiring and editing images to add to your page. Several sites on the web included free images you can use to create your homepage.