#InternetKing here, in my kingdom, it can be difficult knowing what belongs to who, and what others can and can't do with your stuff. That's where licensing comes in. It's a license's job to tell other's stuff about their website. Such as who made it and whether or not people can build off of it.
Choosing a license can be easy if you know what you want, here are some popular public licenses you can use for your website (Note these summaries aren't entirely accurate and aren't a substitute for licenses.):
The MIT license :: Others can do whatever they want with your land as long as they include this license and give you proper credit.
Apache License 2.0 :: Others can do anything but use trademarked material as long as they include this license, copyright, notice, and state changes made to the original content.
And my lesser known license:
Synthesized Public License :: Others can do what they want as long as they keep the copyright and license and don't infringe upon it (example: distributing the project without making any changes), and you don't be mean.
An entire list of open source licenses can be found here:
But what if you don't like any of them? Open up your favorite text editor and make your own! It's that simple, but do note that homemade licenses don't hold up as well as ones with a better reputation, but don't let that discourage you from trying.