Emma Doherty (What I've Learned)

A shallow depth of field makes a portrait with not much contrast much more interesting. 

The camera perfectly captures and focuses on multiple objects in a large depth of field; making your eye naturally go front to back (example: flowers to sedan to truck) 

Architecture with  a shallow depth of field forces you to focus on its details rather than each "layer" of the photo

It perfectly captures contrast with lights (example: fluorescents against a dusky, stormy sky)

It does a great job capturing contrast even in a repetitive photo like this. In this example each object stands out on its own rather then getting confusing.