Sass, Real World example

Sass is CSS just with built in features to make writing it faster. Im not sure what u mean by real world example, but its just CSS. Example - Zurb Foundation is a CSS framework built on SASS. Learn CSS write it alot of it then learn Sass and u'll appreciate what it offers.

once u write sass it will turn into css automagically

In my opinion, sass is a more usable tool, as it has a more conventional approach for a developper. CSS is quite time-eater, where sass can re-use your previous code, nest, write functions and variables, etc... It can become quite handy, especially if you are familiar with other codes. Plain CSS is still usable, that's why it's quite confortable for beginners. (sorry for my english, not my mother tongue).

You're welcome :). A simple example I could give you, is to create a navbar, a responsive one :). Do it with a pure css code, and then try it with Sass, and then with Foundation (you can learn from the new Framework basics course), it uses Sass (or if you prefer Less, you can use Bootstrap, which is also taught in the Framework basics course). It's a perfect (and easier) way to see what you can do with Sass, a lot quicker than with pure CSS. Give us a reply when you do, we can learn from your experience ^^.