One of several top-level domains assigned to URLs of an academic nature, generally for colleges and universities within the U.S. For example, www.pepperdine.edu is the URL for Pepperdine University. Note that .ac is for academic Web sites outside of the U.S. In addition to .edu and .ac, other domain suffixes include .com, .gov, .net, .mil, . .org, and a long list of country code domains. For a list of new suffixes, read the domain name definition.