The Anatomy of a Web Address

URL
http://foo:bar@www.websanity.com:80/calendar/index.php?month=10&week=3#thurs
Scheme

This is commonly referred to as the protocol .

http ://foo:bar@www.websanity.com:80/calendar/index.php?month=10&week=3#thurs
Authority
http:// foo:bar@www.websanity.com:80 /calendar/index.php?month=10&week=3#thurs
User Information
http:// foo:bar @www.websanity.com:80/calendar/index.php?month=10&week=3#thurs
User Name
http:// foo :bar@www.websanity.com:80/calendar/index.php?month=10&week=3#thurs
Password
http://foo: bar @www.websanity.com:80/calendar/index.php?month=10&week=3#thurs
Host
http://foo:bar@ www.websanity.com :80/calendar/index.php?month=10&week=3#thurs
Top-Level Domain
http://foo:bar@www.example. com :80/calendar/index.php?month=10&week=3#thurs
Second-Level Domain
http://foo:bar@www. example .com:80/calendar/index.php?month=10&week=3#thurs
Third-Level Domain

This is commonly referred to as the subdomain . Technically each level of the domain name is a subdomain.

http://foo:bar@ www .websanity.com:80/calendar/index.php?month=10&week=3#thurs
Registered Domain Name
http://foo:bar@www. websanity.com :80/calendar/index.php?month=10&week=3#thurs
Port
http://foo:bar@www.websanity.com: 80 /calendar/index.php?month=10&week=3#thurs
Path
http://foo:bar@www.websanity.com:80 /calendar/index.php ?month=10&week=3#thurs
Path Segment
http://foo:bar@www.websanity.com:80/ calendar /index.php?month=10&week=3#thurs
Path Segment
http://foo:bar@www.websanity.com:80/calendar/ index.php ?month=10&week=3#thurs
Query
http://foo:bar@www.websanity.com:80/calendar/index.php ?month=10&week=3 #thurs
Key-Value Pair
http://foo:bar@www.websanity.com:80/calendar/index.php? month=10 &week=3#thurs
Key
http://foo:bar@www.websanity.com:80/calendar/index.php? month =10&week=3#thurs
Value
http://foo:bar@www.websanity.com:80/calendar/index.php?month= 10 &week=3#thurs
Fragment Identifier
http://foo:bar@www.websanity.com:80/calendar/index.php?month=10&week=3 #thurs

from RFC 3686 — Uniform Resource Identifier (URI): Generic Syntax