Every time your picture is viewed, it uses bandwidth. If you put the picture on this forum for example, and 10 people view it, then you bandwidth use is 10x the size of the image.
For example, say you post a picture of a bird that is 100 kb, and 10 people view it. You have used 1000 kb of your bandwidth. A MB is about 1000 kb (1024 to be exact), so you have used about one mb of your allowed bandwidth.
Another number to be aware of is Gb.. it is about 1000 mb's (1024 to be exact!). So, with this in mind, if you put a 100kb picture up and 100 people view it, you have used up 1 gb of your bandwidth. Luckily when the same person views the picture over and over, it is stored on their harddrive cache, so they do not use more of your bandwidth each time they see your picture.. until they clear their cache/temp files.
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