Analyzing user behavior with computer science methods is common in commercial website design, where a subfield called web analytics uses electronically gathered quantitative data to gain insights about user behavior. Commercial companies use this information for a variety of purposes, from improving search engine performance and customizing a user’s experience to targeting ads in ways that may seem unnerving. What can be done with the information depends on two key factors: (1) what and how information is collected (2) laws, polices, and norms governing the use of information.