Google analytics help to know:
1.) The Bounce rate on your site. Bounce rate is how many visitors exited from the first page. Bounce rate should be smaller in percentage. It simply helps to know whether our website is doing well or not.
2.) Its funnel visualization helps to identify poorly performing pages by tracking landing pages. From this we can change our content and can make it relevant to the users.
3.) The most important thing about Google analytics is that it tells about conversions and goals. It gives a percentage results about the goal conversions.
Google analytics is all about relevancy. If we post relevant data on our site bounce rate will definitely be good.The best way to know about Google analytics is that - create account on Google analytics for your website or blog then check activity on your site. You can best learn it after creating your account.