Structure

Image tags have 6 elements that must be present, even if not used in that particular image: source, height, width, horizontal alignment, vertical alignment, alternate text, and border. The tag itself should look like this:

<IMG SRC="/img/imgname.gif(or jpg)"

HEIGHT="height of image in pixels"
WIDTH="width of image in pixels"
ALIGN="horizontal alignment of image: center, left, right"
VALIGN="vertical alignment of image: top, bottom, center"
ALT="alternate text if image can't/doesn't load"
BORDER="width of border around image, almost always 0">

For more precise placement, and to eliminate preset browser borders, horizontal & vertical space can be specified as well

hspace="horizontal space (in pixels) between image and top border of page"
vspace="vertical space (in pixels) between image and right border of page"

Resources/Guides

WWWColorCalc

ColorMaker

How do they do that with HTML?