Has anyone implemented AJAX into their Wordpress setup on their own?

Or mostly on their own.

I’m trying to do the same. Sort of building a new site while simultaneously trying to learn some new things. I’m looking at this tutorial on dynamically loading posts within a post/page in Wordpress. I may need to re-read over it a few more times to full understand it:

Has anyone successfully followed this tutorial or created some dynamic loading within their Wordpress page?