if you look at an image you don't just see some colors, but your mind creates a whole, three-dimensional image based on things like lighting and most of all also experience. f.e. if you've seen the object once before you know exactly the shape of it, or if you look at a photo of a room your mind knows what a room usually looks like (walls are perpendicular to the floor, etc.) and can create a whole image out of it, which is most likely correct.
This also happens to all objects in this photo. You immediately know what belongs to every object and what all these objects are, which is again hugely based on your experience and things like lighting and other stuff.
A computer, however, just sees some colors and cannot precieve the scene in the same way as you do.
