The extension can tell you if it\\'s a site sponsored by a government agency (.gov), an educational facility (.edu or .ac), an organization (.org), or a commercial enterprise (.com). Once you know that, you can decide if you want to use the information. Government or education sites are more reliable than organizations that may have a bias for or against a particular issue, or commercial sites whose main aim is to sell a product or service. Education sites may sometimes host student work, which would not be appropriate to use; you should check for authorship on those sites.