$是为了提醒开发人员此变量保存对jQuery对象的引用.

$ is to remind developers that this variable holds reference to a jQuery object.

是的，$myList将把选择器应用到的所有元素作为数组保存(尽管它是一个jquery对象，但它像数组一样保存它们)

And Yes, $myList will hold all the element that your selector applied to as an array(although it's a jquery object it just holds them like an array)