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
Researchers traditionally use the terms "morningness" and "eveningness" for the two chronotypes or diurnality and nocturnality in animal behavior. In several countries, especially in Scandinavia, early birds are called "A-people" and night owls are called "B-people".
Etymology.
The term is derived from the primarily nocturnal habits of the owl. Most owls sleep during the day and hunt for food at night.
Characteristics.
Usually, people who are night owls stay awake past midnight, and extreme
the middle of the night, probably while he was staying on the third floor of a rooming house at in Chicago: "...it was a late fall night and raining...I was there naked in the bed and I sprang up. I went to my typewriter and began to write. It was there, under those circumstances, myself sitting near an open window, the rain occasionally blowing in and wetting my bare back, that I did my first writing...I wrote it, as I wrote them all, complete