This is the 809th most frequent Korean word.
아는
"아는" means "knowing" or "that (someone) knows."
In this sentence, '아는' functions as a modifier describing the people I am familiar with.
아는 사람이 많은 모임에 갔어요.
I went to a gathering where I knew many people.
Here, '아는' describes the possession of knowledge by the subject.
그녀는 아는 것이 많아요.
She knows a lot of things.
In this sentence, '아는' is associated with the act of knowing or pretending to know something.