Can you explain Creative Commons to a newbie?

So looking through the marketplace, I see solutions built using various jquery, javascript and php libraries authored and licensed by people other than the marketplace product provider.  Even Dolphin does this.

When I think I have a basic understanding of this, I find something that makes me question said understanding.  

For example, I read on a "human" language friendly guide to using CC products:

"Attribution — You must give appropriate credit, provide a link to the license, and indicate if changes were made. You may do so in any reasonable manner, but not in any way that suggests the licensor endorses you or your use."

 I understand noting changes in their code but does a hyperlink to their license need to be published on a website, visible to the public?  With so many and different licensed products in a Dolphin site with mods ( or even a base version), you would need 1/2 a page dedicated to links to all those license agreements. And I never see that.

So are pretty much most websites out of compliance, and it is so widespread that it kinda is ok? Or is the link that CC site refers to, the link in the header or wherever, simply a text based notice (without a href tag) to the lic agreement?

I understand when Boonex says they purchased redistribution rights for stuff like TinyMCE. I'm asking about stuff like sliders, mail handlers, APIs, etc.

Appreciate your thoughts on this old and tiresome topic.

The license should appear at the top of the php/java/html code in every CC file. It specifically states the license terms which can vary greatly under CC. Provided you retain that license terms at the top of the file, you may usually redistribute the code as part of your package.

   Some vendors may request a hyperlink back to their site, but that's rare and often overlooked. Most are happy with the license being retained at the head of each file.

   As licenses vary, you should pay attention to the license which can often allow code to be distributed with a commercial product.

   That's not the end all, but others can add more comments or tell me I've got it wrong.

https://creativecommons.org/

For context - I am familiar with a copyright infringement issue over a photo which was promoted as public domain when in fact, it was not.  Let me ask in another way....

How much license compliance vetting do you do when you purchase a mod for Dolphin or whatever, to feel confident that a repackaged and sold mod which includes someone else's work will not impact your website weeks, months or more from now if an original author discovers no credit given?

I'm not freaking out or hyper-sensitive to infringement issues, just wanting to get a feel for how others approach this.  While the CC org website does a good job of explaining why sharing is good for this world, I can't seem to find the more definitive answer/example I think I'm looking for. I see strategic verbiage but little tactical information. Perhaps I'm just overthinking it.

Anyway, it's all good.  I consider myself a student teaching myself what I can, when I can.  Appreciate the responses so far and any more to follow on this topic. But don't spend a lot of time on answering. I know you are busy.