Ever wonder what that ‘.gif’ extension on some of the picture files you have on your personal computer strands for? Yes we all know that it is some kind of name for some kind of picture, but what exactly?

Well GIF stands for Graphics Interchange Format. It is a trademarked format that is defined as “A standard defining a mechanism for the storage and transmission of raster-based graphics information ….. it allows high-quality, high-resolution graphics to be displayed on a variety of graphics hardware and is intended as an exchange and display mechanism for graphics images.”.

The Graphics Interchange Format or GIF is a format that enjoys wide support and portability and is therefore used extensively and widely over the internet. The GIF format was initiated by Compuserve 20 years ago and has a 256 color limitation, or an 8 bit per pixel bitmap image format. The fact of the color limitation (only 256 colors) makes this format inappropriate color photos, rather it is more suitable for graphics and such images and symbols as logos etc. The GIF format is also suitable for a animations. In other words this format is more suited to simple images rather than more complex images such as photographs.

The reason for this is something called lossless compression, this shows up sharp demarcations or lines in a picture. Whereas a photograph would have many different colors and hues, light and shade and gradations of color, other images such as animations, graphics, logos etc would have sharp-edged line art and lesser color complexity thereby making them more conducive to this format. If this format is used for film it would result in a low resolution film.

There is an interesting story as regards the pronunciation of the acronym GIF. Normally one would pronounce GIF with a G for goat sound, however the designers of the format wanted that it should be pronounced with a J sound as in G for George. The story goes that a popular brand of peanut butter called Jif was running some commercials which the GIF creators were spoofing: “choosy developers choose GIF”. Both pronunciations are correct though; and one can pronounce the word either way.

When the GIF format was created, a 256 color palette did not seem at all inadequate and given hardware limitations that existed in the mid eighties (this format came into being in 1987). In the event format worked very well considering the existing technology and requirements. There were methods developed to diffuse photographs by using pixels of 2 or more different colors to approximate an in-between color to increase the range and complexity of the color palette. This is known as dithering however by this method, the image unavoidably loses some detail. More recently, the Portable Networks Graphic (PNG) format is gaining popularity as a replacement for the Graphics Interchange Format. This is because this format has better compression techniques than GIF and wider color palette. The PNG format can store additional color depth and more transparency information than GIF.