I use Google Analytics for my website.
Site Overlay (Click Density Analysis): is a powerful feature in Google Analytics. It provides insights into how your visitors interact and navigate your website. You can understand which content is found interesting by your visitors.
Goals (Task Completion Rates): is the primary metric for measuring how well your site fulfills your objectives to have a website. This might not be as easy for every type of website. If you have a site that the main objective is to sell a product or a service, then the “Thank you” page after the visitor finalizes their purchase is your goal. Easy to measure. If you have a site that provides information, this might get tricky.
Advance Segments (Segmented Visitor Trends): is in beta. It lets you segment your visitors and analyze their behavior. It is a powerful tool, since a visitor coming to your site might have a different interaction with your site than a visitor coming from a search engine.