The study showed that the most popular images generally include a landscape or an animal, something that commands inspiration (such as a setting sun) and something that adds humor or simply triggers an emotion. The photograph must also have the right type of lighting and not be blurred.
"Emotion and quality are what really count, according to our study," says Dr. Paul Piff, who led the research team. All these elements make photographs attractive and gain them 'likes.'
To reach these conclusions, UC Berkeley asked 500 people throughout Europe to look at 35 pictures in a random order. They then asked them to imagine whether or not they would give them a 'like' if each of the photos appeared in their Facebook feed.