HTML Uniform Resource Locators

● URL stands for Uniform Resource Locators, which is another name for the web address.

● It is actually a specific character string that creates an orientation to an internet resource.

● It is an address of documents and other resources on the World Wide Web. Along with identifying the location of a document and web resources, it also works in specifying the tool to access that address through a web browser.

The address bar of any browser contains URL, which shows the location of a webpage you are viewing on the browser.

The Web browser requests web pages from the web servers using a specific URL.

It looks something like this:

https://en.wikipedia.org/wiki/HTML

The syntax of URL is:

scheme://prefix.domain:port/path/filename

Scheme

It defines the type of internet service used to access internet resources. It is always followed by :// (one colon and two slashes). The most common scheme names or protocols are http://, https:// and ftp://

Prefix

It defines a domain prefix like where resource is located. It is actually a combination of the local name and the parent’s domain name of the host.

For example, www.wikipedia.org, where www is the prefix or hostname, and wikipedia.org is the domain name.

Domain

It defines the domain name of the host, such as wikipedia.org

Port

It defines the port number at the host. Servers often deliver multiple services, so you need to tell your server what service you have requested which is done using the port number. The default port number for http is 80.

Path

It defines a path at the server, which is done by identifying the particular resource in the host that you want to access. If it is not defined, it will take the root directory of the site.
For example: /wiki/HTML

Filename

It defines the name of a document or other resource. The default filename of an HTML URL can be the default.asp, index.html or anything depending on the settings of the server.

Some common URL Schemes

http – HyperText Transfer Protocol, which is used for common web pages and are not encrypted

https – Secure HyperText Transfer Protocol, which is used for secure web pages and are encrypted

ftp – File Transfer Protocol, which is used for downloading or uploading files

file – This scheme is used for a file on your computer.

You must also know that URL Scheme and host components are not case-sensitive, but the path is case-sensitive. Commonly, the complete URL is defined in lower case.