<img src="http://upload.wikimedia.org/wikipedia/en/a/a3/Bobdobbs.png"> <img src="http://upload.wikimedia.org/wikipedia/en/a/a3/Bobdobbs.png" height="162" width="108">Gets you:
<img src="http://mumble.com/image.jpg"> substitute the actual source of the image for http://mumble.com/image.jpg This image must be out on a server on the web someplace, not on your machine. This is why people have flicker and picassa accounts. You can easily vary the size of a given image by specifying it. The native size of the J. R. "Bob" Dobbs picture is 324x216. It is best to keep your scaling to powers of 2 (as shown) to minimize scaling artifacts. Remember that scaling up will not introduce new detail into the existing picture.
In terms of specifying the scaling, the above is mostly overkill. It's nice to specify the height in both dimensions as this gives the browser some notion of how big you want the picture to be rather than having to wait for it to download to know what the image size is. This allows the browser to do a partial rendering of the page while waiting for the missing image. If you just want to scale an existing image, providing only a single dimension will get the browser to calculate the missing dimension for you, but it can't do that till the image comes in.
Stationary images usually end with .jpg or some variation. Moving images on this forum are only possible using images which end in .gif The .gif format allows for short sequences of stationary images to be presented like a very tiny movie. Currently the forum does not appear to allow embedded video.
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