This is the 16543rd most frequent Korean word.
사람
Person; human.
Here, '사람' is used to refer to a specific individual or person.
그 사람은 정말 재미있는 이야기꾼이에요.
That person is a truly interesting storyteller.
In this case, '사람들' is the plural form of '사람,' referring to people in general.
사람들은 모두 친절해야 합니다.
People should all be kind.
The term '사람' ('어떤 사람') is used to refer to an unspecified individual or people in a general sense.