Set up (web)
The Analytics tracking code collects data for your web property, and returns that data to Analytics where you can see it in reports. When you add a new web property to your Analytics account, Analytics generates the tracking code snippet that you need to add to the pages whose data you want to collect. You can use this tracking code snippet as is, or customize it to collect additional data. The tracking code snippet contains a unique ID for the web property that lets you identify that property's data in your reports.