URI vs URL

In this article, we will learn what is URI, what is URL and URI vs URL. Let’s start!!!

What is a URI?

A URI, or Uniform Resource Identifier, is a string identifier that refers to an internet resource. It is a string of characters used to identify any resource on the internet based on its location, name, or both.

A URI has two subsets: URL (Uniform Resource Locator) and URN (Uniform Resource Name) (Uniform Resource Number). If it only contains a name, it is not a URL. In the real world, we mostly see URLs and URNs rather than direct URIs.

HTTP, HTTPs, ftp, Idap, telnet are common URI schemes.

URI Syntax:

1. Scheme:

Scheme can be any combination of letter, digit, plus sign, or hyphen (-), followed by a colon (:). The most common protocols are http, file, ftp, data, and irc. The schemes must be registered with the Internet Assigned Numbers Authority (IANA).

2. Authority:

The authority component is optional and is denoted by two forward slashes (/).

• userinfo: It may include a username and, optionally, a password separated by a colon. The @ symbol comes after the sub-component.
• host: It either has a registered name or an IP address. The IP address must be surrounded by [] brackets.
• port: Optional

3. Path:

It is made up of a series of path segments separated by a slash(/). It is always specified by the URI; however, the specified path may be empty or of 0 length.

4. Query:

It is an optional component, denoted by a question mark (?). It contains a non-hierarchical query string.

5. Fragment:

It is also an optional component that is preceded by the hash(#) symbol. It is made up of a fragment identifier that points to a secondary resource.

Example of URI: news:comp.infosystems.www.servers.unix

What is a URL?

A URL, or Uniform Resource Locator, is used to locate a resource on the internet. It is a resource reference as well as a method of accessing that resource. A URL always represents a unique resource, which could be an HTML page, a CSS document, an image, or something else.

A URL accesses a resource via a protocol, which can be HTTP, HTTPS, FTP, or others.

It is primarily referred to as the website’s address, which a user can find in their address bars.

URL Syntax:

1. Scheme:

The first component of the URL is a scheme, which represents a protocol that a browser must use to request the resource. HTTP or HTTPS are the most commonly used protocols for websites.

2. Authority:

The authority consists of two sub-components, separated by a colon: domain name and Port. The domain name can be anything, and the port is the technical gate through which the resource is accessed on a web server. HTTP is accessed via port 80, while HTTPS is accessed via port 443.

3. Path:

The path specifies the full path to the web server resource. It could be something like /software/htp/index.html.

4. Query String:

The name and value pair are contained in the string. When used in a URL, it follows the path component and provides the information. For example, “?key1=value1&key2=value2”.

5. Fragment:

It is also an optional component that is preceded by the hash(#) symbol. It is made up of a fragment identifier that points to a secondary resource.

Difference between URI vs URL:

1. URI contains both URL and URN to identify a resource’s name and location or both; URL, on the other hand, is a subset of URI and only identifies the resource’s location.
2. The URI example is urn:isbn:0-476-27557-4, while the URL example is https://google.com.
3. We can use URI to locate resources in HTML, XML, and other files, whereas we can use URL to find a web page.
4. Each URL can be a URI, but not all URIs can be URLs.

Comparison between URI and URL:

Summary:

In this article, we looked at the concept of URI and URL, and also the syntax of each. We looked at the differences between URI and URL, and also a tabular comparison between URI and URL.