This is the 4th most frequent Korean word.
있는
"있는" means "existing," "there is," or "having."
Here, '있는' indicates the presence of books within the room, showing existence or possession.
저는 책이 있는 방에 들어갔어요.
I entered the room where there are books.
In this sentence, '있는' describes people having time, indicating possession.
주말에 시간이 있는 사람은 저에게 연락 주세요.
Those who have time on the weekend, please contact me.
In this context, '있는' refers to websites that possess or contain information, combining possession with a descriptive adjective.