Walk Score (www.walkscore.com) is a publicly-available tool that rates the walkability (ease of walking and biking) of U.S. neighborhoods and communities as defined by their zip codes. The current version of the software measures the straight-line or "crow-fly" distance to nearby destinations and amenities (e.g. businesses, grocery stores, parks, etc.). While a unique and cutting-edge tool, Walk Score's utility can be increased by improving the accuracy of the distance measures it uses and by demonstrating its association with health-related outcomes, such as physical activity levels and obesity. This study will test Walk Score's ability to predict health-related outcomes using a series of existing datasets across a variety of age groups. Using the results of these analyses, researchers will identify evidence-based enhancements to Walk Score and make recommendations to the developer of the program (Front Seat).