URIs, URLs, and URNs | Difference between URI and URL | URL Explained

Summary

This video by the Web Dev Cave clarifies the confusion between URIs, URLs, and URNs. It explains that URI stands for Uniform Resource Identifier, used to identify resources on the internet either by name or location. URLs, or Uniform Resource Locators, specify the location of a resource, while URNs, Uniform Resource Names, denote the name. The video also delves into the components of a URL, including protocol, domain, port, path, query strings, and fragments, illustrating how they work together to locate web resources.

Takeaways

• 🔍 URI stands for Uniform Resource Identifier, used to identify a resource on the internet by location, name, or both.
• 📍 URL stands for Uniform Resource Locator, which is a type of URI that specifies the address or location of a resource.
• 🔖 URN stands for Uniform Resource Name, another type of URI that specifies the name of a resource.
• 🤔 The distinction between URI, URL, and URN can be confusing, but understanding them is useful for web development.
• 🌐 URI can include both the name and location of a resource, whereas URLs use just the location and URNs use just the name.
• 🌐 Every URL is a URI, but not every URI is a URL, as URIs can also be URNs.
• 💻 URLs are commonly used in web browsers to locate web pages and are composed of required components like protocol and domain, and optional components like port, path, query strings, and fragments.
• 🔗 The protocol part of a URL specifies the method of access, such as HTTP or HTTPS.
• 🏠 The domain or IP address in a URL identifies where the resource is located on the internet.
• 🚪 Ports in URLs are optional and specify the network connection point, with default ports being used if none is specified.
• 📁 The path in a URL is optional and helps locate the specific file or directory on the server.
• 🔑 Query strings in a URL are used to pass information from the client to the server, encoded as key-value pairs.
• 📚 Fragments in a URL point to a specific part of a webpage, indicated by the hash symbol and used for direct navigation within the page.

Q & A

What does URI stand for?

URI stands for Uniform Resource Identifier.

What is a URI used for?

A URI is used to identify a resource on the internet either by location, by name, or both.

How is a URI different from a URL?

A URL (Uniform Resource Locator) is a type of URI that specifically refers to the address or location of a resource. All URLs are URIs, but not all URIs are URLs.

What does URL stand for?

URL stands for Uniform Resource Locator.

What information does a URL provide?

A URL provides the address or location of a resource on the web.

What is a URN and how does it differ from a URL?

URN stands for Uniform Resource Name, and it is a URI that specifies the name of a resource. Unlike URLs, URNs do not specify the location of the resource.

Can a URI specify both the name and the location of a resource?

Yes, a URI can specify both the name and the location of a resource.

Why is it more common to use URLs rather than URNs to locate resources?

It is more common to use URLs because they specify the location of a resource, making it more effective for identifying and accessing resources on the web.

What are the two required components of a URL?

The two required components of a URL are the protocol used to connect and the domain or IP address to connect to.

What optional components can a URL have?

A URL can have optional components such as the path, port, query strings, and fragments.

What is the purpose of the port number in a URL?

The port number in a URL specifies the type of connection point used by the TCP/IP protocol and the connecting computer.

How are query strings used in a URL?

Query strings are used to pass information from the client to the server, typically as key-value pairs.

What are fragments in a URL and how are they used?

Fragments in a URL are used to request a specific portion of a web page and are identified by a hash symbol (#) before the fragment identifier.