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Understanding of URL || Uniform Resource Locator


Every document on the Web has a unique address. This address is known as Uniform Resource Locator (URL).

Several HTML/XHTML tags include a URL attribute value, including hyperlinks, inline images, and forms. All of them use the same syntax to specify the location of a web resource, regardless of the type or content of that resource. That's why it is known a Uniform Resource Locator.

URL Elements
A URL is made of up several parts, each of which offers information to the web browser to help find the page. It is easier to learn the parts of a URL, if you look at the example URL given below, there are three key parts: the scheme, the host address, and the file path. The following section will discuss each of them:
http://www.codebites.com/index.htm

The Scheme
The scheme identifies the type of protocol and URL you are linking to and therefore, how the resource should be retrieved. For example, most web browsers use Hypertext Transfer Protocol (HTTP) to pass information to communicate with the web servers and this is the reason a URL starts with http://.

The Host Address
The host address is where a website can be found, either the IP address (four sets of numbers between 0 and 255, for example 68.178.157.132 ) or more commonly the domain name for a site such as www.tutorialspoint.com. Note that "www" is not actually part of the domain name although it is often used in the host address.

The File Path
The filepath always begins with a forward slash character, and may consist of one or more directory or folder names. Each directory name is separated by forward slash characters and the filepath may end with a filename at the end. Here index.htm is the filename which is available in html directory:
https://www.codebites.com/html/index.htm


Absolute and Relative URLs
You may address a URL in one of the following two ways:

1 Absolute − An absolute URL is the complete address of a resource. For example http://www.codebites.com/html/html_te...

2 Relative − A relative URL indicates where the resource is in relation to the current page. Given URL is added with the base element to form a complete URL. For example /html/html_text_links.htm