What's the difference between a jQuery object and a DOM element? Difference between .get() and .index()?

Question

I\'m lead to this question when trying to figure out the difference between jQuery\'s .get() and .index(), I\'ve looked over the jQuery API and I s

Answer 1

DOM is not the structure of the page such as below

 etc.

DOM is only a representation of the page
Loosely speaking, DOM is a kind of an Object-Oriented Programming Language, which enables you to access and manipulate on the actual document.

document.getElementById("a") 
/* here document is an object and getElementById is an method of it */ 

To be more precise, DOM is an interface rather than an programming language and it's language independent. It happened to be included in Javascript.