HAHAHAHA....you wish. Actually, I do too, but there simply aren't any hard and fast rules, so I'll try to give you the best guidelines that I can instead. Your best bet is to check with the image over there -->
By Domain and please note that this only applies to American websites as different countries have their own domain (eg .ca for Canada)
.com
Commercial site. The information provided by commercial interests is
generally going to shed a positive light on the product it promotes.
While this information might not necessarily be false, you might be
getting only part of the picture. Remember, there's a monetary
incentive behind every commercial site in providing you with
information, whether it is for good public relations or to sell you a
product outright.
.edu
Educational institution. Sites using this domain name are schools
ranging from kindergarten to higher education. If you take a look at
your school's URL you'll notice that it ends with the domain .edu.
Information from sites within this domain must be examined very
carefully. If it is from a department or research center at a
educational institution, it can generally be taken as credible. However,
students' personal Web sites are not usually monitored by the school
even though they are on the school's server and use the .edu domain.
.gov
Government. If you come across a site with this domain, then you're
viewing a federal government site. All branches of the United States
federal government use this domain. Information such as Census
statistics, Congressional hearings, and Supreme Court rulings would be
included in sites with this domain. The information is considered to be
from a credible source.
.org
Traditionally a non-profit organization. Organizations such as the
American Red Cross or PBS (Public Broadcasting System) use this domain
suffix. Generally, the information in these types of sites is credible
and unbiased, but there are examples of organizations that strongly
advocate specific points of view over others, such as the National Right
to Life Committee and Planned Parenthood. You probably want to give
this domain a closer scrutiny these days. Some commercial interests
might be the ultimate sponsors of a site with this suffix.
.mil
Military. This domain suffix is used by the various branches of the Armed Forces of the United States.
.net
Network. You might find any kind of site under this domain suffix. It
acts as a catch-all for sites that don't fit into any of the preceding
domain suffixes. Information from these sites should be given careful
scrutiny.
