i have 4 sizes of jpg for each image stored on the server, it works well for me.
why do any kind of dynamic resizing, when space on the server is relatively cheap.
I agree. The rationale was that it would be simpler, which does not make much sense.
3. I definitely wouldn't serve a larger image and let the browser resize it. Consider a 1MB image... and 50 concurrent users. You're going to need a 100Mb connection to serve them in a decent timeframe. Resizing them server side on *every* request just doesn't make sense.
IMO the point of having smaller images is that you do it once (even client side if you will), but it will be served more than once, so it makes sense to do it.
I see your point. Processing the same thing over and over is crazy. Seems like the best solution is to use multiple sizes stored on the server. It is automatically the least demanding of both server and client resources and really has no real down side.