Some are better at counting heads and creating reports that focus on customers' behavior patterns. Many of the products help you group customers who exhibit similar purchasing habits and demographics into segments. Segments are often far less obvious, though. Analytics software helps you discover them. Other products are better at monitoring traffic and creating maps of a Web sites' choke points.
Several packages exhibit strength in parsing data into activity based on a specific product.
Analytics also allows marketers to identify groups of individuals for targeting and testing. A relatively large B2C Web site will get 100 million hits per day. Web servers log about 200 bytes of data for each hit. That amounts to about 20GB of raw data per day. High-profile sites today keep customer data or summary versions of it around for about three years, creating a demand for huge amounts of storage and significant processing power to manipulate this warehouse of data.