What does it do?Essentially, Google Analytics provides with all the information you could ever want about how people interact with your website. It tells you things such as:
What can you do with it?You can use it to help figure which are your most successful pages (and with a bit of brain work, perhaps you can figure out why). You can use it to analyse the heaviest sources of traffic to your site – so you can then go all out maximising those sources' potential, or you can focus on sadder, lonelier sources that need a little more attention (do you need to put more effort into your keyword research? Or do you need to start plastering guest posts all over the web to get those referral links?).
Once you've gotten to grips with Google Analytics, you can really start taking advantage of its capabilities.
You run a business, so you're almost certainly interested in conversions (and if you're not, how are you still in business?). Google Analytics allows you to track and analyse conversions, letting you see what's working and what's not.
For example, you can set goals that allow you to measure how well your site is doing in certain areas, such as how many people visit your “thanks for registering!” page (so you know how many people are signing up to your email list successfully -- and, more importantly, if there's a problem that's stopping them), or how many people are actually downloading that free ebook you've got slapped up on your site.
Google Analytics is a vital tool for all businesses with a website. And best of all, it's free, so it'd be well worth your time to take an afternoon to get to grips with it and install it on your site. You'll be tracking conversions and figuring out to increase your sales in no time!