YSK: Small talk is a very important preface to a conversation, as you can use it to guage a person's personality, mood, and level of extraversion, making choosing a topic to talk about significantly easier.
from /r/YouShouldKnow
YSK：閒聊是談話的一個非常重要的前奏，因爲你可以通過閒聊來猜測一個人的性格、情緒和外向程度，使選擇談話的話題變得明顯容易。