(View this example at "original" size)

This is the Photoshop (or Elements) Image Size dialog box, exhibiting numbers
typically seen when first opening a fairly large image (such as an ex-camera one).

NOTE: The Resolution figure that you first see ex-camera could be 72, 180, 300 or just about anything at all!! For on-screen viewing,
be it directly on your own monitor, a projector, or via the World Wide Web, this number is COMPLETELY IRRELEVANT.

Much confusion has arisen over the initial Resolution setting (defined by a Tag within ex-camera image files), and various
camera manufacturers have their own pet idea of what this should be. Again, it is stressed that this figure
-- a token starting point only, chosen by the manufacturer -- is irrelevant for on-screen viewing.

What we are interested in here is ONLY the "Pixel Dimensions" shown in the first two fields of this dialog box.

As we are going to re-sample (downwards) the image for ideal Web viewing, the "Resample
Image" check-box must be checked, as shown here, before proceeding further.
(It may be already checked, or not, upon opening this dialog, depending on previous usage.)
"Constrain Proportions" must also be checked unless you want to deliberately distort your image.