The following KB articles relate to this topic:
Google Analytics is a free service offered by Google which allows website administrators and editors to view specific metrics for their webpages. This tool is especially helpful for those looking to determine their site's most popular pages, what people are searching for on the site, the average time spent on the site, which browsers or devices their users are accessing the site from, etc.
It is not required that you use this tool, however, it can be incredibly insightful. Many of our websites are currently utilizing Google Analytics. Follow the KB instructions to add this feature to your website.