What's a good primer on "large scale" economics?

I don’t have a practical immediate use for the information, but I’d like to have a better grasp of what economic changes on a national and global scale actually affect and how. I get the feeling I’m not the only one.

Can you recommend a book, essay, or even a website if it actually goes in depth that could give me the basics in plain language?

I know it’s a lot to sum up in one source, but I’m not looking to get into global banking, or even finance, just educate myself.

Thanks.