Now there are hundreds of image formats, although only a handful are actually appropriate for internet. And to make things even more confusing, there are additional ways to display pictures including Java, ActiveX, Dynamic HTML and so on (although these tend to just display variations on standard web graphics formats).

And if that wasn't bad enough, email and newsgroups never evolved a real, built-in standard for images. These two formats are text based and have remained so in spite of changes in browsers and technology. Special encoding technology has been created to allow attachments to be sent with messages. Most of modern email clients detect this and perform conversion automatically.

For web, dominant formats are GIF and JPEG. BMP (bit mask images) are occasionally used, and up-and-coming PNG format seems poised to threaten GIF in a few years. The GIF format is perhaps oldest and most powerful of formats (except for limitation of 256 colors), since it supports animation, interlacing and transparency. The other dominant format, JPG, tends to create smaller, albeit fuzzier images.

The three major web formats for graphics are described briefly below.

GIF (Graphics Interchange Format) - This is probably most widely used format on internet. It was created by CompuServe in 1987 to display images on their service. Some of great features of this graphics format include:

- Excellent compression - images created in GIF format can be optimized to very small sizes.

- Interlacing - Allows images to "fade" in slowly. This is very useful for large images.

Some people actually debate need to keep visitors on your web site for any length of time. I have heard argument that it doesn't matter how long they stay - you really just want them to purchase something and then leave. Unless you have created a very specific, extremely targeted, one or two page web site, then that thinking is hogwash.

Look, you've gone to a lot of work to create a wonderful web site. You have tons of great content for people to look at. Perhaps you have some awesome products to sell or a message to get across. The longer that people stay, more likely they are to see your message or purchase your products. You can almost translate length of their stay directly to interest in what you've got to say.

So how do you get people to stay on your site for any length of time? Well, you include great content which is linked together in such a way as to pull people deeper into your site. Give them plenty of ways to explore what you've got.

Don't design your site as one huge long page. Remember that you are creating a web site, so split those long pages up into short articles and link them together logically. Your visitors like seeing one or two screen's worth of information at a time ... any more and they will just not scroll down to see it.