Invideo teaches more about depth of field to help make your videos more cinematic. 

0:00- What makes depth of field so important
0:45- Understanding depth of field
1:05- What is deep depth of field
1:35- What is shallow depth of field
3:00- What is rack focus and how can it be used?
3:43- How to create depth of field by manipulating the aperture settings in your camera?