Don't Have to be a Computer Genius to...
Use a GIF versus a JPEG!!!
So, you were just getting comfortable using acronyms such as AOL amd WWW. Even HTTP and HTML roll right off the tongue. Think you've really mastered the computer lingo? I thought I had until I decided to create my own webpage. I had to wade through a litany of new terms, such as...FTP, CGI, ASP, XML, SMTP and POP. Just when I thought I'd conquered them all, I realized it was just the beginning. If you really want your website to look professional you have to learn how to use images and if you want to use images you have to understand GIFs and JPEGs. I broke out my Photoshop5.5. and do you know what I discovered?...YOU DON'T HAVE TO BE A COMPUTER GENIUS TO...Use a GIF versus a JPEG!!!
The cardinal rule of web design is to make sure your web pages download quickly. A fast, basic website will win hands-down over a slow, beautiful website every time. Images are often to blame for slow downloads. Before using an image or several images on a page, you will need to "compress" the images so they take up as little file size as possible. In fact, your whole web page, including images should probably not exceed 40k (kilobytes). Two universally used Internet Graphics formats are GIF and JPEG. There are differences between the two worth learning.
GIF: GIF stands for Graphics Interchange Format, and is pronounced with a hard "g" as in "gh-i-f" (though some people pronounce it with a soft "g" as in "j-i-f." That distinction could warrant an article of its own!) A GIF is a "lossless" format which means the program that creates a GIF compresses the original image so that it does not lose any data. A GIF uses a simple substitution method of compression, which, to mere mortals, means that a flat colored image (with lots of repetition) will compress better than a more complex, non-repetitive image. The bottom line is that large areas of pixels that are all exactly the same color are compressed very efficiently by GIF.
JPEG stands for Joint Photographic Experts Group, the original name of the committee
that wrote the standard, and is pronounced "jay-peg." JPEG is a "lossy"
format which means that the decompressed image isn't quite the same as the original.
Basically, a JPEG saves space by throwing away parts of the image. A JPEG achieves
much greater compression than is possible with "lossless" methods
like a GIF. JPEG is designed to be read by the inexact human eye. Thus, JPEG
is intended for compressing images that will be looked at by humans, not machines.
Small errors introduced by JPEG are virtually undetectable by the naked eye.
NOTE: The human eye is more sensitive to brightness (gray scale data) variations
than to hue variations. JPEGs can compress the hue variations more.
The degree of "lossiness" can be varied by adjusting compression parameters. This means that you can trade off file size for image quality. You can make "extremely" small files if you don't mind poor quality and conversely, if you aren't happy with the output quality, you can lessen the compression settings to increase the output quality.
When to Use GIF Format
to Use JPEG Format
Copyright © 2000-2001 Marlene Hollander. All rights reserved.