Making a website accessible globally through the World Wide Web (www) requires some pretty special technology. Some large companies will do it themselves because their web traffic will justify it.
However, the vast majority of smaller websites are rendered on the www through a 'hosting provider'. There are many.
So what happens is you rent some server space from a hosting provider. Again, it's very inexpensive and a minimum plan for about €6 per month is more than enough for even a bunch of small websites and blogs, if that's where things end up for you.
And again, I use the Minimus plan from Blacknight Solutions and it's fine.
I chose the Windows 2008/IIS 7 version because I could see no good reason why the Linux service would be any better for my purposes.
Once you do that you will have an account and access to your dashboard. Make sure to keep a note of passwords, etc, and don't make them easily guessable!
From there you can configure and manage your websites.
But before uploading and configuring your website you will need to download and configure the WordPress site / blog files on your local computer. I'll cover that next and it's easy enough! We'll be downloading directly from wordpress.org rather than using the inbuilt installer on Blacknight.
When you have WordPress all configured on your local computer you will need to upload those files to your newly-rented host server space with an FTP client (also easy!) and we'll cover that too.
For Irish readers this article in Silicon Republic gives some recent key statistics about .ie domain registrations which aspirant Irish site owners might find interesting.
Comments very welcome, thank you!