There are two different types of graphic images that file formats must interpret: drawing programs use vector images, while painting programs use bitmapped images. 

• Vector Images. When you draw something in a vector-image drawing program, the program translates your instructions into mathematical equations, which then tell the program what image to produce. 
  
  
• Bitmap Images. Bitmap, or raster images, are created with a series of dots. When you draw something in a bitmap painting program, the program creates the image with a series of dots that make up the picture. Paint image files are typically larger than drawing (vector) files. 

• .GIF, or Graphics Interchange Format. GIF is the most common graphics format found on the Internet, a

  Before giving it all up for fame on Saturday Night Live, the late Phil Hartman was a graphic designer. One of his jobs included creating the logo for Crosby, Stills, Nash and Young.

  nd the best online format for illustrations. It compresses and stores graphics files for quick transfer and is best for solid color graphics like clip art and logos, including animated clip art. Most of the basic buttons, icons and lines you would need for a website are in GIF format. GIF files are smaller and easier to transfer than most other formats, but are not the best way to store sophisticated images such as photographs, which will usually contain more than the 256 colors a GIF is capable of handling. GIF images are 8-bit (as in millions of colors), 256 colors, but newer versions include 24-bit and 16 million-color capability.

• .JPEG, or Joint Picture Experts Group. JPEG (sometimes written as .JPG) files compress photographic or natural images of up to 24-bit color. JPEG is a "lossy" format, which means that it must downgrade the image quality slightly by removing small pieces in order to reduce the file size. The difference is slight and you can adjust the compression to improve the image. Use JPEG for photographic images or natural artwork rather than flat-colored illustrations, logos or lettering typically handled by GIF format. Many website backgrounds and borders are also done in JPEG format. JPEG images are 24-bit with 16 million-color capability.

• .PNG, or Portable Network Graphic. This format is capable of handling much more sophisticated images, but often requires plug-ins (additional software, usually free) to work properly. PNG can handle images up to 48-bits and 256 colors, and may be supported by some web browsers, but JPEG and GIF are the most common web-based formats.

• .ART is a clip art graphics format that uses several compression devices to determine the best method for translating the image based on color, size, and whether or not the image is a photograph or synthetic. Depending on the image, the ART format can reduce some files to smaller sizes than the GIF or JPG formats can. 

• .BMP, or Bitmap Image File. Created by Microsoft, this is a common image format for PCs and is often used for line drawings created in PC-based paint programs. 

• .PCX. This is a graphics format typically used in PC-based Paintbrush programs. 

• .TGA, or Truevision Targa. This format is used with systems that use Truevision video boards and MS-DOS-based color applications. 

• .TIF, or Tagged-Image File. TIF (sometimes written as TIFF) is used to transfer large, high-quality, high-resolution images. Similar to GIF and JPEG in its capabilities, TIF is commonly used for desktop publishing, faxing, and 3-D image applications.