I just found a great app on Google Chrome (not on Firefox which I previously used for Garden.org).
If you go onto the main page for Google Chrome, click on the App icon (a bunch of multicolored dots), go into the Web Store search EXIF, then download the free App called EXIF Viewer (by Rodriguez).
Now if you hover over a photo you have opened in it's own window, at the top the app tells you some of the "metadata" or "EXIF" about the photograph. It generally includes what camera (important due to sensor size but they don't directly tell you sensor size), what focal length lens, the ISO, Aperture and shutter speed, and whether a flash was used (some photographers block this info so it does not always work).
I can look at a photo I like, and then get an idea how they did it. Wow!
