Links on a page pull in new text, but not changing page – Help?

So I don’t even know what this is called, but I have a site where the client would like to have the links on a page display new text when clicked, while staying on the same page. Not anchors or jumps. They are short blurbs. I want to avoid iFrames. Also, hoping that the client can update the text through WP.

This is a good example:
https://www.dhtmlgoodies.com/scripts/ajax-dynamic-articles/ajax-dynamic-articles.html

Any suggestions would be greatly appreciated… Jay