Hi, Madmaxx! My friend, Bazboy 247 below answered your question well. I'll just say, don't worry about it, if you can. Take care, my friend!

gosh never heard of that a bit beyond me

Barry did a great job of explaining. I found an article that might interest you:

http://www.nimblehost.com/blog/2012/11/why-cruftless-links-are-better/

If your using Wordpress you don't need to worry about it
Cruftless links are used to simplify the url of index.html pages and files when you are building websites in a web editor like Dreamweaver or rapid weaver
Unless you intend to design your website from scratch in html you do not need to worry about it because you can use permalinks in Wordpress to simplify your website urls
It makes urls SEO friendly

Barry