The technology exists for ecommerce merchants to track where their visitors live. Digital Element is a firm that provides this geo-tracking service, which allows merchants to change their home pages and other landing pages based on, say, whether a visitor lives in Alaska or Florida. The technology behind this service is IP addresses. Every computer on the Internet has an IP address and, in this follow up interview, we asked Digital Element co-founder and executive vice president Rob Friedman what, exactly, is an IP address. He joins Practical eCommerce’s Kerry Murdock.