Javascript：使用jQuery作为参数的匿名函数

Question

I'm looking at a JavaScript plug-in for the first time, their instruction directs one to include referencing the jQuery API in the head of a HTML document.

The first line of JS in their plug-in entails what I've come to understand is a self-invoking anonymous function

(function($) {...} )(JQuery);
// ... represents many lines of script

1. Is an actual jQuery object being passed as an argument?
2. And to be clear, the $ is just an variable/object name receiving jQuery?

I've only been working with JS for about a year. Thanks!

Answer 1

function a(){} -> this return a function object

(function a(){}) -> this is a function object

(function a(){})(...) -> call that function object to run with or without args

So it's just like a function call after all.