URL and Domain Names

The Internet structure of the WWW (World Wide Web) is built on a set of rules called HTTP (Hypertext Transfer Protocol) and a page description language called HTML (Hypertext Markup Languages).

HTTP uses Internet addresses in a special format called a URL (Uniform Resource Locator). URL looks like:


here, type: specifies the type of server in which the file is located, address is the address of the server, and path tells the location of the file on the server. For example, in the URL given here:


Here, http: specifies the type of server, codescracker.com is the address of the server and java/java-loop.htm is the path of the file java-loop.htm


A URL specifies the distinct address for each resource on the Internet.

Domain Name

An Internet address which is character based is called a Domain Name.

Internet Servers and their Description

Here the table given below lists the Internet Servers and tells what they provide:

Server Protocol Information Provides
ftp File Transfer Protocol Text and binary files that are organized in a hierarchical structure, much like a family tree
gopher Transfer Control Protocol/Internet Protocol (TCP/IP) Text and binary files that are organized in a menu structure
http Hypertext Transfer Protocol Hypertext/hypermedia files, that is, multimedia documents that contain links to images, sounds, or other multimedia documents on the World Wide Web
mail Post Office Protocol (POP) Version 3 and Simple Mail Transfer Protocol (SMTP) Messages sent via electronic mail
news Network News Transfer Protocol (NNTP) Newsgroups that are organized in a hierarchical structure.

Common Domains List

Here is a table lists the most common domains with their affiliation and remarks:

Domain ID Affiliation Remarks
com Commercial for commercial firms
edu Education for educational firms
gov Government for government organizations
mil Military for Military
net Network Resources for ISPs/networks
org Usually non-profit organizations for NGOs and other no-profit
co Company for listed companies
biz Business for business
tv Television for television companies and channels

Popular Country Abbreviations

Sometime a two letter abbreviation indicating a country name may be used. For example,


Here the last in suggests that it is based in India (.in)

Here are the list of some common country abbreviations:

Abbreviation Country Name
au Australia
ca Canada
dk Denmark
fr France
in India
jp Japan
nz New Zealand
uk United Kingdom

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