What is an Internet address?
As you have learned how messages are transmitted from one computer to another, every computer in the Internet must have a unique and specific address. An Internet or IP address, as it is sometimes called, consists of four numbers separated by periods. The smallest address would be 0.0.0.0 while the biggest would be 1234.5678.9101.1121. Don't worry, only computers are expected to remember all these numbers without getting confused. For humans, we use the Domain Name System (DNS).
What are domains?
Like IP addresses which are numerical, the alphabetical domain names are also separated by periods or dots. Thus, the U.S. Library of Congress will have an IP address of 140.147.248.7 and the domain name will be www.loc.gov.
Domain names have the format: hostname.subdomain.top-level-domain. My school's domain name, for example, is ocean.otr.usm.edu. This naming structure will give you clues about the address. Ocean is the name of the host computer, otr stands for "Office of Technology Resources" which manages the system, usm is the abbreviation for University of Southern Mississippi, the sub-domain, and edu signifies that this is an educational institution. The gov for the Library of Congress indicates it is a government institution.
Here are the existing top-level domains in the Internet:
- com - commercial
- .edu - educational
- .net - network
- .org - organization
- .gov - government
- .mil - military
Other countries sometimes add their codes at the end, such as .au for Australia, .ph for Philippines, and .fr for France, th for Thailand.
