下面pattern中的问号和括号有特殊作用吗？不太懂

Question

var text = "mom and dad and baby";

var pattern = /mom( and dad( and baby)?)?/gi;

var matches = pattern.exec(text);

alert(matches.index); // 0

alert(matches.input); // "mom and dad and baby"

alert(matches[0]); // "mom and dad and baby"

alert(matches[1]); // " and dad and baby"

aler t(matches[2]); // " and baby"

Answer 1

这是正则表达式吧，问号在量词元字符后面表示取消贪婪模式，即在满足条件下，尽可能少地匹配。