One of early problems on net was how to display graphics. The first browsers only displayed textual information - modern browser with it's images, multimedia and plugin's did not exist. Everything was text based.
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.
- Transparency - The ability to make a color be transparent, allowing background of web page to show through.