The IMG SRC tag allows you to place an image in your document. The image file, generally a GIF file, can be either an inline image or an external one. An inline image is a graphic that is actually on the page. There are choices as to where the image is placed and whether surrounding text is aligned with the image's t op, middle, or bottom. It allows the name of the image to be displayed by non-graphical browsers or browsers where graphics are turned off.
External images can exist in one of many formats and can be downloaded by a non-graphical browser.
The images discussed above are passive. It is possible to have more fun and add more interest with active or clickable images. Rather than inflicting several 200K or more of graphical files on the reader, a simpler low-overhead preview catalog is displayed. Each thumbnail might only occupy 5K or 10K, maki ng your presentation far more tolerable to the reader. Another nice feature of HTML active-image processing is the mappable image.