One uses regular HTTP, while the other uses a secure version of this scheme. Websites just started using this to indicate the user is using the World Wide Web. However, how the domain name is set up is based on how the web server and network administrators set it up in the backend. Most users access the internet via a web browser, which inserts port 80 on HTTP connections behind the scenes.
A different network port could still be specified to make the connection to a particular destination. You can append user input, query parameters, or values to a URL depending on the configuration of the web server where that particular resource is hosted on. Finally, the following URL demonstrates a fragment identifier, more commonly known as a query string:.
This is saying that to use the HTTP protocol to send a request to the web resource at google. This is why you'll sometimes see an extremely long URL as many variables are being sent to the web server in more interactive Web applications or dynamic pages like a search engine. A broad range of other fragments is also used to specify the details of a destination, such as the hashtag that directs the user to a specific view of a page.
URLs can be redirected or forwarded to a different URL in several ways, the most common of which are permanent and temporary. URLs can also be shortened by activating a shortening service that uses a redirect on a short-named domain.
This is particularly useful in case of lengthy URLs containing many queries. It is formally specified in RFC By: Justin Stoltzfus Contributor, Reviewer. By: Satish Balakrishnan. Dictionary Dictionary Term of the Day. Natural Language Processing. Techopedia Terms. Connect with us. Sign up. Term of the Day. Best of Techopedia weekly. News and Special Offers occasional. Full Bio. Kathy: "Is that your dog? You, sir, are a pedant. Show 4 more comments.
Active Oldest Votes. Examples Roger Pate This is my name, which is an identifier. I say "like" because these examples do not follow the required syntax. Improve this answer. Community Bot 1 1 1 silver badge. Roger Pate Roger Pate. Roger's answer provides good pragmatic advice. URL is an informal concept, not a formal concept. And the confusion dates back to a "classical view" which tried to rigidly distinguish between categories of URI of which URL was one category.
So in other words, there is no such thing as a "relative" URL? Show 2 more comments. SamB 8, 5 5 gold badges 44 44 silver badges 53 53 bronze badges.
Jon Skeet Jon Skeet 1. It depends on the interpretation of the RFC. For example in Java the URI parser does not like [ or ] and that's because the spec says "should not" and not "shall not". AdamGent: RFC 1. Doesn't it? AdamGent: That sounds like a Java implementation quirk, and not normative. The java. And java. I think this just means the Java Standard Library has some inconsistent class behavior.
JonSkeet Maybe just need to differentiate between standards vs implementations? RFC excerpt. But existing implementations may not match the spec exactly, possibly for interoperability, and may use URLs that are not valid per the RFCs. And because it's a complicated area, some people and documents might use 'URL' to mean something different from the RFC-specified thing.
Show 12 more comments. URN -- Uniform Resource Name Identifies a resource by a unique and persistent name, but doesn't necessarily tell you how to locate it on the internet. It usually starts with the prefix urn: For example: urn:isbn to identify a book by its ISBN number. Do any browsers actually know how to fetch documents by URN?
Not that I know of, but modern web browser do implement the data URI scheme. Stephen Ostermiller Stephen Ostermiller Although browsers do generally handle non-URL formatted file paths.
Mozilla publishes their test cases for file URLs. See section 1. It allows different types of resource identifiers to be used in the same context, even when the mechanisms used to access those resources may differ. It allows uniform semantic interpretation of common syntactic conventions across different types of resource identifiers This answer is a lot more easy to understand. And for anyone to read more about this Daniel Miessler's blog post linked in the comment above misses this point.
Add a comment. Greg Greg I choose a format that I believed would be more familiar to readers. So would it make sense to say that the hash e. URI is a resource on the current domain, so it needs less information to be found. Air 7, 2 2 gold badges 48 48 silver badges 83 83 bronze badges. Phil Sturgeon Phil Sturgeon This answer may be over-simplified but look at the context of his question. It will be more helpful to him that waffling on about XML namespaces! This answer is not only wrong but actively misleading.
Both examples are URLs. This is the difference as far as CodeIgniter is concerned. This is wrong. It is a "relative-ref", which is a kind of "URI-reference". See Section 4. CodeIgniter's probably using the terms wrong and that should be called out; the Q as currently edited isn't framed as CodeIgniter-specific. For future people who read these comments and are as confused as I was: This answer wasn't posted for this question.
This question never had anything to do with CodeIgniter. There was a duplicate question which specifically mentioned CodeIgniter which was closed and had all of its answers migrated over to this question.
This answer was one of those which were moved from the old closed question to this protected question. Even so, I this answer is misleading. I have downvoted it - others should do the same since, in its new home, it is wrong. The author should delete it or the merge be undone.
Show 5 more comments. Eugen Konkov A small addition to the answers already posted, here's a Venn's diagram to sum up the theory from Prateek Joshi's beautiful explanation : And an example also from Prateek's website :. Gustavo Mori Gustavo Mori 7, 3 3 gold badges 35 35 silver badges 51 51 bronze badges. I believe the second illustration is incorrect. By the specification url.
So, posts fragment identifier could be part of the URL — ruvim. The two illustrations contradict each other. Shouldn't url be - thinkzarahatke. Please explain it to me I am vey confused. Misleading, if not wrong. Premraj Premraj Minor quibble: There should be a colon between [domain] and [port].
IE: example. I have to wonder: how does one retrieve the resource associated with a mailto URL? Your answer is incorrect and obscure. If you need 20 examples to exemplify a definition, your definition is not clear. There are two basic subsets: URLs, which define location especially to a browser trying to look up a webpage and URNs, which define the unique name of something.
If I'm way off base, please let me know! Brad Turek 1, 1 1 gold badge 25 25 silver badges 48 48 bronze badges. Kevin Lowe Kevin Lowe 5 5 silver badges 2 2 bronze badges. No, I think you're right. Craig Wilson Craig Wilson See this question which has many references to the specs: Are square brackets permitted in URLs?
When square brackets appear in either, they should be encoded. Mark Cidade Mark Cidade I thought it was the other way around. It is only true that they are the same thing because the definition of URL has changed over time. SFEley 7, 5 5 gold badges 26 26 silver badges 31 31 bronze badges. Maybe I missed that part, but I don't see any reference in the provided link to them removing the distinction between URL and URI, only acknowledging the confusion and wanting specs that are incorrectly referencing URL to be updated to reference URI instead.
Adiii Adiii Amal Murali Peter Boughton Peter Boughton k 30 30 gold badges silver badges bronze badges. Sujit Sujit 3, 9 9 gold badges 38 38 silver badges 50 50 bronze badges. Stephen Ostermiller Swapnil Swapnil 2 2 silver badges 5 5 bronze badges. Please refer for more details: Wikipedia. Peter Mortensen 29k 21 21 gold badges 97 97 silver badges bronze badges. Prashanth Sams Prashanth Sams This doesn't teach me anything that's not covered by the other answers that are at least 6 years old, and which are much more complete and actually try to explain how to distinguish URIs from URLs.
It is important to note that the image is a Venn diagram even though it doesn't look like a typical one. I've seen people try to interpret it as "parts of the URL".
Gumbo Gumbo k gold badges silver badges bronze badges. Specifically, a URL is a type of URI that identifies a resource via a representation of its primary access mechanism e. It's not an extremely clear term, really. Here is my simplification: URN: unique resource name, i. This answer is wrong. Furthermore, the link in this answer is broken and I can not find a suitable replacement.
Bruno Bronosky Bruno Bronosky Mischa Mischa 7 7 silver badges 13 13 bronze badges. This answer is misleading. I found: A uniform resource identifier URI represents something of a big picture. Rakeeb Rajbhandari Rakeeb Rajbhandari 4, 6 6 gold badges 41 41 silver badges 74 74 bronze badges.
Do you recall the source for where you found this? Was it Wikipedia or somewhere else? It is okay if it is Wikipedia! I am not trying to be difficult about attribution but rather, I am asking because your answer is different than this one , and I think that your answer is correct. The answer is ambiguous. In Java it is frequently used in this way: An Uniform Resource Locator URL is the term used to identify an Internet resource including the scheme http, https, ftp, news, etc.
Freeman Freeman 5, 3 3 gold badges 42 42 silver badges 46 46 bronze badges.
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