" Lark, also called early chronotype, is someone who does usually wake up very early. They are most active during morning around 6:00 am. Approximately 10% of people are larks.

Owl, also called late chronotype, is someome who does usually wake up very late. They are most active in the evening around 6:00 pm. They usually drink a lot of coffee and accumulate a massive sleep debt as they go through life. Approximately 10% of people are owls.

The rest, around 80% of people, are hummingbirds. Some hummingbirds are more larkish, some more owlish and some are in between. "

― John Medina , Brain Rules: 12 Principles for Surviving and Thriving at Work, Home, and School