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Here are some considerations though.
Your ISP may not allow you to run a public server and they may block Port 80. Also you may have to look into DNS and consider things like dynamic versus static IP and how to point your server to a URL. You will also need to register the URL if you want a top-level (normal looking) domain.
But the reality is that you can have a public website complete with a funky URL which will point directly to a folder on your computer where your website is hosted. If you have a basic HTML editor and basic HTML knowledge you can have that index.html file public in no time!
You'll want to go to Users>(your user name)>Sites> and there should be a landing page that looks like this.
You can also go via your Harddrive>Library>Webserver and you will see this same page. One will be your public live website, and the other should be a folder for your backup files. They can both contain the same thing.

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