The .gov domain is restricted to websites related to the U.S. government.
On these sites, you will find reports, news, statistics, and other updates related to the government and the activities of its branches.
A related domain is .mil, which covers the U.S. military.
The .edu domain is used only by "U.S. postsecondary institutions that are institutionally accredited by an agency on the U.S. Department of Education's list of Nationally Recognized Accrediting Agencies." Typically, these sites will contain scholarly information.
You might find reports on original research, statistics, or links to an online repository containing publications by the institution's faculty or other unique content.
The .org domain was originally created to house the websites of nonprofit organizations, but there is no longer any restriction on who can register a .org site.
Nonprofit organizations might provide reports or other publications on their websites.
Some companies might use the .org domain to give the impression they are a nonprofit organization. The IRS provides a search tool that lists all organizations that are eligible to receive tax-deductible charitable contributions—try this tool if you are unsure about the status of a company.
The .com domain was originally used for commercial websites (ones that were used to sell a product or service), but the domain is now unrestricted so it can be used by anyone.
Because you'll find such a wide range of information and content in this domain—personal websites, company homepages, commercial sites, etc.—it is essential that you evaluate your results carefully.
There are many other possible domain endings on the Internet. Some are not recommended for use in academic research, e.g., .biz, which serves commercial businesses, or .xxx, which... you know.
Some other domains contain potentially valuable information, such as the .int domain, which represents international intergovernmental organizations or treaty-based organizations.
Also, look out for geographic domains. These two-letter codes usually indicate a website that comes from a country other than the U.S. (although some U.S. sites use .us and some international sites use .com).
If you have a website with an unfamiliar domain, check it against the IANA master list of domains.
Depending on your field of study, you will find some web sources that you just need to bookmark—reliable, frequently updated sources that contain valuable data, articles, reports, and publications on the cutting edge of your field.
The website's domain will give you a clue about the person, company, or organization that hosts the information. To the right, you'll find information about some of the most commonly used domains, as well as reputable examples.
Look for subject-specific website recommendations from librarians on your subject's Research Guide.
Some examples:
Try looking at pages for the professional societies in your field of study. Not only are these pages potential resources for your research, but you also may find curated lists of reliable web sources on particular topics.
Look for information on professional societies on your subject's Research Guide, or ask your professors for suggestions.
Some examples of professional societies: