I am a night owl, I am more an evening person and tend to stay up late at night. Yesterday I went to bed at 5:30am 
wow! yeah I like staying up late too. I worked 3rd shift for many years
Wow! I love the term night owl because owls are my favourite animals. The term actually came from the nocturnal habits of owls.
yeah, owls are pretty cool creatures
I a an extreme night owl, because I stay awake until just before or after dawn. However most nightowls can be considered people who stay awake past midnight 
yeah, you dont have to stay up all night to be a night owl. maybe even before midnight.
tend to have unhealthier eating habits.
Some night owls with great difficulty adopting normal sleeping and waking times may have delayed sleep-phase disorder. Morning light therapy may be helpful in shifting sleep rhythms for the night owl.
Factors.
The tendency to be a night owl exists on a spectrum, with most people being typical, some people having a small or moderate tendency to be a night owl, and a few having an extreme tendency to be a night owl. An individual's own tendency can change over
Night owl (person)
A night owl, evening person or simply owl, is a person who tends to stay up until late at night, or the early hours of the morning. Night owls who are involuntarily unable to fall asleep for several hours after a normal time may have delayed sleep phase syndrome. 
The opposite of a night owl is an early bird – a lark as opposed to an owl – which is someone who tends to begin sleeping at a time that is considered early and also wakes early.