Definition of different graphic format

The Bitmap Image File (BMF) or a Bitmap, is a graphics image file format used to store bitmap digital images independently of display device. The term map comes from the computer programming terminology, meaning just a map of bits.

Size:	508 × 400                                  Size: 511 x 388
Type:	17KB PNG                                      Type: 10 KB GIF

When a bitmap displays a colored image, such as a lake scene, there are several shades of gradation in colors and lighting. In this case, each pixel in the bitmap might have 16, 24, or 48 bits of information associated with it. The more bits, the greater the resolution of the bitmap – and the larger the file.

Joint Photographic Experts Group or JPEG

It is a standardised image compression mechanism. It works well on photographs, naturalistic artwork, and similar material; not so well on lettering, simple cartoons, or black-and-white line drawings. JPEG handles only still images, but there is a related standard called MPEG for motion pictures. It is the most common image format used by digital cameras and other photographic image capture devices and also storing and transmitting photographic images on the World Wide Web.

Graphics Interchange Format or GIF

It is a bitmap image format that was introduced by Compuserve in 1987 and has since come into widespread usage on the World Wide Web due to its wide support and portability. GIF supports up to 8 bits pixel thus allowing a single image to a palette of up to 256 distinct colors.

(a glittering tweety and a painted puffy in GIF)

It also supports animations and allows a separate palette of 256 colors for each frame. However, the color limitation makes the GIF format unsuitable for reproducing color photographs and other images with continuous color, but it is well-suited for simpler images such as graphics or logos with solid areas of color.

Portable Networks Graphics or PNG (pronounced “ping”)

It is a bit mapped image format and video codec that employs lossless compression data. PNG was created to improve upon and replace GIF (Graphics Interchange Format) as an image-file format not requiring a patent license. The motivation for creating the PNG format came early 1995, when there were problems with the GIF format which made a replacement desirable, notably its limit of 256 colours at a time when computers were able to display far more than 256 colors were growing common.

a normal PNG image

a PNG image created Diana Todd using various 2D and 3D tools

sources:

wikipedia: http://en.wikipedia.org/wiki/JPEG

http://en.wikipedia.org/wiki/PNG

http://www.wisegeek.com/what-is-the-difference-between-bitmap-jpeg-and-gif-files.htm