You can limit your search results in Google to pages from a specific domain by adding site:(domain name) to the end of your search.
For example, to find information about the effects of exercise on diabetes patients published only by government agencies, you would search diabetes and exercise site:gov.
You can even limit your results to pages found at a single site.
For example, to search for information on the same topic found on the Centers For Disease Control and Prevention page (http://www.cdc.gov), you would search diabetes and exercise site:cdc.gov.
A URL (Uniform Resource Locator) is a web address for a page or document on the World Wide Web. We can make some educated guesses (see the box at right for a warning) about the reliability of a web site if we know a little about URLs.
Each URL (for example https://www.whitehouse.gov/get-involved/internships/), consists of an access protocol (http),a domain name (www.whitehouse.gov), and an optional path to a file or resource residing on that server (get-involved/internships).
The domain name indicates the organization responsible for the site (www.whitehouse.gov in the example above). The top-level domain indicates the type of site (gov in the example above).
The most common top-level domains and the type of site they indicate are:
In general, .gov and .edu web sites are more reliable than .com web sites. The box at left describes how to limit a Google search to only .gov sites.
Making educated guesses about the reliability of web sites will only get you so far--you must rigorously evaluate web sites on an individual basis, be they a .com or .gov. How do we evaluate web sites? Click the Evaluation Criteria tab above for guidance.