Images...

Before the introduction of Broadband, the majority of web users connected to the internet via dial-up phone connections - up to 56kbps. Many of these sites had a limited number of pictures or graphics, which resulted in fast download times.

However, when Broadband was introduced and businesses started allowing direct access to the internet for their employees, so too did the speeds at which users could access the web (512kbps and higher). Unfortunately, with the increased bandwidth available to users, the number of images / graphics and ultimately the size of web sites has also increased.

Some company logos or banners contain fonts which are not supported on the web, and must be included as graphics (rather than text). In hind-sight, it would have been preferable to create two versions (printed media and electronic/web versions) or simply use a "best-representation" for the font by using one of the built-in supported web-fonts.

Many web design companies these days, use graphics unnecessarily (for navigation or rollover effects) or use graphics which aren't optimised for the web. Newer browsers support a wide range of built in effects to simulate rollover effects. Some companies even use the wrong format for a graphics object - choosing JPEG instead of GIF (and vice versa).

Image optimisation aims to minimise the size in bytes of a graphics file, without degrading the quality of the image to an unacceptable level. The reduction in file size allows more images to be stored in a given amount of disk or memory space. It also reduces the time required for images to be sent over the Internet or downloaded from Web pages.

There are several different ways in which image files can be compressed. For Internet use, the two most common compressed graphic image formats are the JPEG format and the GIF format. The JPEG method is more often used for photographs, while the GIF method is commonly used for line art and other images in which geometric shapes are relatively simple. Another new method that may in time replace the GIF format is the PNG format.