Most people who really want to get into photography eventually feel the need to learn their f/stops and shutter speeds. And although we do advocate this, we believe that the best photo is not necessarily the one with the best histogram, but the one which communicates best. This is often achieved through good composition.
Always ask yourself does the image communicate? What does it communicate? Is it beautiful to look at? And if it is beautiful and something that you want to look at and admire, does it matter what camera and what f/stop the photographer used? Because even if you had this information, it doesn't mean that you would be able to replicate that photo.