If you use the image server instead of FTP upload the viewers of your webpage will download the pictures directly from your computer, instead of your webserver. If your have few viewers (less than one viewer pr. captured image) on your webpage, this will mean less bandwith used. Also, the user viewing your webcam picture will always be served a newly taken picture.
Although FTP is the most common way of updating a website and webcams, using an image server is actually more bandwith-effective in most cases.
The disadvantage of using an image server is that there's no picture when the webcam is offline.
