I came across a website with a blog post teaching all how to clear cache for web development purposes. My personal favourite one is to do /? on the end of a web address at the URL bar.
Are there any more little codes like that? if so what are they and where can I find a cheat sheet?
Appending /? may work for some URLs, but not for all.
It works if the server/site is configured in a way that, for example, http://example.com/foo and http://example.com/foo/? deliver the same document. But this is not the case for all servers/sites, and the defaults can be changed anyway.
There is no name for this. You just manipulate the canonical URL, hoping to craft a URL that points to the same document, without getting redirected.
Other common variants?
I’d expect appending ? would work even more often than /? (both, of course, only work if the URL has no query component already).
http://example.com/foo
http://example.com/foo?
You’ll also find sites that allow any number of additional slashes where only one slash used to be.
http://example.com/foo/bar
http://example.com/foo////bar
Not sure if it affects the cache, but specifying the domain as FQDN, by adding a dot after the TLD, would work for many sites, too.
http://example.com/foo
http://example.com./foo
Some sites might not have case-sensitive paths.
http://example.com/foo
http://example.com/fOo
Related
In my application I have localized urls that look something like this:
http://examle.com/en/animals/elephant
http://examle.com/nl/dieren/olifant
http://examle.com/de/tiere/elefant
This question is mainly for Facebook Likes, but I guess I will hit similar problems when I start thinking about search engine crawlers.
What kind of url would you expect as canonical url? I don't want to use the exact english url, because I want that people clicking the link will be forwarded to their own language (browser setting/dependent on IP).
The IP lookup is not something that I want to do on every page hit. Besides that I would need to incorporate more 'state' in my application, because I have to check wether a user has already been forwarded to his own locale, or is browsing the english version on purpose.
I guess it will going to be something like:
http://example.com/something/animals/elephant
or maybe without any language identifier at all:
http://example.com/animals/elephant
but that is a bit harder to implement, bigger chance on url clashes in the future (in the rare case I would get a category called en or de).
Summary
What kind of url would you expect as canonical url? Is there already a standard set for this?
I know this question is a bit old, but I was facing the same issue.
I found this:
Different language versions of a single page are considered duplicates only if the main content is in the same language (that is, if only the header, footer, and other non-critical text is translated, but the body remains the same, then the pages are considered to be duplicates).
That can be found here: https://developers.google.com/search/docs/advanced/crawling/consolidate-duplicate-urls
From this I can conclude that we should add locales to canonicals.
I did find one resource that recommends not using the canonical tag with localized addresses. However, Google's documentation does not specify and only mentions subdomains in another context.
There is more that that language that you need to think of.
It's typical a tuple of 3 {region, language, property}
If you only have one website then you have {region, language} only.
Every piece of content can either be different in this 3 dimensional space, or at least presented differently. But this is the same piece of content so you'd like to centralize managing of editorial signals, promotions, tracking etc etc. Think about search systems - you'd like page rank to be merged across all instances of the article, not spread thinly out.
I think there is a standard solution: Canonical URL
Put language/region into the domain name
example.com
uk.example.com
fr.example.com
Now you have a choice how you attach a cookie for subdomain (for language/region) or for domain (for user tracking)!
On every html page add a link to canonical URL
<link rel="canonical" href="http://example.com/awesome-article.html" />
Now you are done.
There certainly is no "Standard" beyond it has to be an URL. What you certainly do see on many comercial websites is exactly what you describe:
<protocol>://<server>/<language>/<more-path>
For the "language-tag" you may follow RFCs as well. I guess your 2-letter-abbrev is quite fine.
I only disagree on the <more-path> of the URL. If I understand you right you are thinking about transforming each page into a local-language URL? I would not do that. Maybe I am not the standard user, but I personally like to manually monkey around in URLs, i.e. if the URL shown is http://examle.com/de/tiere/elefant, but I don't trust the content to be translated well I would manually try http://examle.com/en/tiere/elefant -- and that would not bring me to the expected page. And since I also dislike those URLs http://ex.com/with-the-whole-title-in-the-url-so-the-page-will-be-keyworded-by-search-engines my favorite would be to just exchange the <language> part and use generic english (or any other language) for <more-path>. Eg:
http://examle.com/en/animals/elephant
http://examle.com/nl/animals/elephant
http://examle.com/de/animals/elephant
If your site is something like Wikipedia, then I would agree to your scheme of translating the <more-part> as well.
Maybe this Google's guidelines can help with your issue: https://support.google.com/webmasters/answer/189077?hl=en
It says that many websites serve users (across the world) with content targeted to users in a certain region. It is advised to use the rel="alternate" hreflang="x" attributes to serve the correct language or regional URL in Search results.
I have a product page with options in select list (ex : color of the product etc...).
You accede to my product with different urls :
www.mysite.com/product_1.html
www.mysite.com/product_1.html#/color-green
If you accede with the url www.mysite.com/product_1.html#/color-green, the option green of the select list is automatically selected (with javascript).
If i link my product page with those urls, is there a risk of duplicate content ? Is it good for my seo ?
thx
You need to use canonical urls in order to let the search engines know that you are aware that the content seems duplicated.
Basically using a canonical url on your page www.mysite.com/product_1.html#/color-green to go to www.mysite.com/product_1.html tells the search engine that whenever they see www.mysite.com/product_1.html#/color-green they should not scan this page but rather scan the page www.mysite.com/product_1.html
This is the suggested method to overcome duplicate content of this type.
See these pages:
SEO advice: url canonicalization
A rel=canonical corner case
At one time I saw Google indexing the odd #ed URL and showing them in results, but it didn't last long. I think it also required that there was an on page link to the anchor.
Google does support the concept of the hashbang (#!) as a specific way to do indexable anchors and support AJAX, which implies an anchor without the bang (!) will no longer be considered for indexing.
Either way, Google is not stupid. The the basic use of the anchor is to move to a place on a page, i.e. it is the same page (duplicate content) but a different spot. So Google will expect a #ed URL to contain the same content. Why would they punish you for doing what the # is for?
And what is "the risk of duplicate content". Generally, the only onsite risk from duplicate content is Google may waste it's time crawling duplicate pages instead of focusing on other valuable pages. As Google will assume # is the same page it is more likely to not event try the #ed URL.
If you're worried, implement the canonical tag, but do it right. I've seen more issues from implementing it badly than the supposed issues they are there to solve.
Both answers above are correct. Google has said they ignore hashtags unless you use hash-bang format (#!) -- and that really only addresses a certain use case, so don't add it just because you think it will help.
Using the canonical link tag is the right thing to do.
One additional point about dupe content: it's less about the risk than about a missed opportunity. In cases where there are dupes, Google chooses one. If 10 sites link to your site using www.example.com and 10 more link using just example.com you'll get the :link goodness" benefit of only 10 links. The complete solution to this involves ensuring that when users and Google arrive at the "wrong" on, the server responds with an HTTP 301 status and redirects the user to the "right" one. This is known as domain canonicalization and is a good thing for many, many reasons. Use this in addition to the "canonical" link tag and other techniques.
When should a trailing slash be used in a URL? For example - should my URL look like /about-us/ or like /about-us?
I am fully aware of the SEO-related issues - duplicate content and the canonical thing; I'm trying to figure out which one I should use in the context of serving pages correctly alone.
For example, my colleague is thinking that a trailing slash at the end means it's a "folder" - a "directory", so this is not a correct style. But I think that without a slash in the end - it's not quite correct either, because it almost looks like a folder, but it isn't and it's not a normal file either, but a filename without extension.
Is there a proper way of knowing which to use?
It is not a question of preference. /base and /base/ have different semantics. In many cases, the difference is unimportant. But it is important when there are relative URLs.
child relative to /base/ is /base/child.
child relative to /base is (perhaps surprisingly) /child.
In my personal opinion trailing slashes are misused.
Basically the URL format came from the same UNIX format of files and folders, later on, on DOS systems, and finally, adapted for the web.
A typical URL for this book on a Unix-like operating system would be a file path such as file:///home/username/RomeoAndJuliet.pdf, identifying the electronic book saved in a file on a local hard disk.
Source: Wikipedia: Uniform Resource Identifier
Another good source to read: Wikipedia: URI Scheme
According to RFC 1738, which defined URLs in 1994, when resources contain references to other resources, they can use relative links to define the location of the second resource as if to say, "in the same place as this one except with the following relative path". It went on to say that such relative URLs are dependent on the original URL containing a hierarchical structure against which the relative link is based, and that the ftp, http,
and file URL schemes are examples of some that can be considered hierarchical, with the components of the hierarchy being separated by "/".
Source: Wikipedia Uniform Resource Locator (URL)
Also:
That is the question we hear often. Onward to the answers! Historically, it’s common for URLs with a trailing slash to indicate a directory, and those without a trailing slash to
denote a file:
http://example.com/foo/ (with trailing slash, conventionally a directory)
http://example.com/foo (without trailing slash, conventionally a file)
Source: Google WebMaster Central Blog - To slash or not to slash
Finally:
A slash at the end of the URL makes the address look "pretty".
A URL without a slash at the end and without an extension looks somewhat "weird".
You will never name your CSS file (for example) http://www.sample.com/stylesheet/ would you?
BUT I'm being a proponent of web best practices regardless of the environment.
It can be wonky and unclear, just as you said about the URL with no ext.
I'm always surprised by the extensive use of trailing slashes on non-directory URLs (WordPress among others). This really shouldn't be an either-or debate because putting a slash after a resource is semantically wrong. The web was designed to deliver addressable resources, and those addresses - URLs - were designed to emulate a *nix-style file-system hierarchy. In that context:
Slashes always denote directories, never files.
Files may be named anything (with or without extensions), but cannot contain or end with slashes.
Using these guidelines, it's wrong to put a slash after a non-directory resource.
That's not really a question of aesthetics, but indeed a technical difference. The directory thinking of it is totally correct and pretty much explaining everything. Let's work it out:
You are back in the stone age now or only serve static pages
You have a fixed directory structure on your web server and only static files like images, html and so on — no server side scripts or whatsoever.
A browser requests /index.htm, it exists and is delivered to the client. Later you have lots of - let's say - DVD movies reviewed and a html page for each of them in the /dvd/ directory. Now someone requests /dvd/adams_apples.htm and it is delivered because it is there.
At some day, someone just requests /dvd/ - which is a directory and the server is trying to figure out what to deliver. Besides access restrictions and so on there are two possibilities: Show the user the directory content (I bet you already have seen this somewhere) or show a default file (in Apache it is: DirectoryIndex: sets the file that Apache will serve if a directory is requested.)
So far so good, this is the expected case. It already shows the difference in handling, so let's get into it:
At 5:34am you made a mistake uploading your files
(Which is by the way completely understandable.) So, you did something entirely wrong and instead of uploading /dvd/the_big_lebowski.htm you uploaded that file as dvd (with no extension) to /.
Someone bookmarked your /dvd/ directory listing (of course you didn't want to create and always update that nifty index.htm) and is visiting your web-site. Directory content is delivered - all fine.
Someone heard of your list and is typing /dvd. And now it is screwed. Instead of your DVD directory listing the server finds a file with that name and is delivering your Big Lebowski file.
So, you delete that file and tell the guy to reload the page. Your server looks for the /dvd file, but it is gone. Most servers will then notice that there is a directory with that name and tell the client that what it was looking for is indeed somewhere else. The response will most likely be be:
Status Code:301 Moved Permanently with Location: http://[...]/dvd/
So, totally ignoring what you think about directories or files, the server only can handle such stuff and - unless told differently - decides for you about the meaning of "slash or not".
Finally after receiving this response, the client loads /dvd/ and everything is fine.
Is it fine? No.
"Just fine" is not good enough for you
You have some dynamic page where everything is passed to /index.php and gets processed. Everything worked quite good until now, but that entire thing starts to feel slower and you investigate.
Soon, you'll notice that /dvd/list is doing exactly the same: Redirecting to /dvd/list/ which is then internally translated into index.php?controller=dvd&action=list. One additional request - but even worse! customer/login redirects to customer/login/ which in turn redirects to the HTTPS URL of customer/login/. You end up having tons of unnecessary HTTP redirects (= additional requests) that make the user experience slower.
Most likely you have a default directory index here, too: index.php?controller=dvd with no action simply internally loads index.php?controller=dvd&action=list.
Summary:
If it ends with / it can never be a file. No server guessing.
Slash or no slash are entirely different meanings. There is a technical/resource difference between "slash or no slash", and you should be aware of it and use it accordingly. Just because the server most likely loads /dvd/index.htm - or loads the correct script stuff - when you say /dvd: It does it, but not because you made the right request. Which would have been /dvd/.
Omitting the slash even if you indeed mean the slashed version gives you an additional HTTP request penalty. Which is always bad (think of mobile latency) and has more weight than a "pretty URL" - especially since crawlers are not as dumb as SEOs believe or want you to believe ;)
When you make your URL /about-us/ (with the trailing slash), it's easy to start with a single file index.html and then later expand it and add more files (e.g. our-CEO-john-doe.jpg) or even build a hierarchy under it (e.g. /about-us/company/, /about-us/products/, etc.) as needed, without changing the published URL. This gives you a great flexibility.
Other answers here seem to favor omitting the trailing slash. There is one case in which a trailing slash will help with search engine optimization (SEO). That is the case that your document has what appears to be a file extension that is not .html. This becomes an issue with sites that are rating websites. They might choose between these two urls:
http://mysite.example.com/rated.example.com
http://mysite.example.com/rated.example.com/
In such a case, I would choose the one with the trailing slash. That is because the .com extension is an extension for Windows executable command files. Search engines and virus checkers often dislike URLs that appear that they may contain malware distributed through such mechanisms. The trailing slash seems to mitigate any concerns, allowing the page to rank in search engines and get by virus checkers.
If your URLs have no . in the file portion, then I would recommend omitting the trailing slash for simplicity.
Who says a file name needs an extension?? take a look on a *nix machine sometime...
I agree with your friend, no trailing slash.
From an SEO perspective, choosing whether or not to include a trailing slash at the end of a URL is irrelevant. These days, it is common to see examples of both on the web. A site will not be penalized either way, nor will this choice affect your website's search engine ranking or other SEO considerations.
Just choose a URL naming convention you prefer, and include a canonical meta tag in the <head> section of each webpage.
Search engines may consider a single webpage as two separate duplicate URLS when they encounter it with and without the trailing slash, ie example.com/about-us/ and example.com/about-us.
It is best practice to include a canonical meta tag on each page because you cannot control how other sites link to your URLs.
The canonical tag looks like this: <link rel="canonical" href="https://example.com/about-us" />. Using a canonical meta tag ensures that search engines only count each of your URLs once, regardless of whether other websites include a trailing slash when they link to your site.
The trailing slash does not matter for your root domain or subdomain. Google sees the two as equivalent.
But trailing slashes do matter for everything else because Google sees the two versions (one with a trailing slash and one without) as being different URLs.
Conventionally, a trailing slash (/) at the end of a URL meant that the URL was a folder or directory.
A URL without a trailing slash at the end used to mean that the URL was a file.
Read more
Google recommendation
I usually like defining my pages to know exactly what page does what. However, on a number of sites, I see where the filename is hidden from view and I was just a little curious.
Is there any specific benefit of having URLs appear like this:
http://mydomain/my_directory/my_subdirectory/
As opposed to this:
http://mydomain/my_directory/my_subdirectory/index.php
Thanks.
Done correctly it can be better for:
the end user, it is easier to say and remember.
SEO, the page name may just detract from the URL in terms of search parsing.
Note: In your example (at least with IIS) all that may have happened is you've made index.php the default document of that sub directory. You could use both URLs to access the page which could again affect SEO page rank. A search engine would see both URLs as different, but the page content would be the same, resulting in duplicate content being flagged. The solution to this would be to:
301 redirect from one of the URLs to the other
Add a canonical tag to the page saying which URL you want page rank to be given to.
Some technologies simply don't match url with files. Java Servlet for examples.
These are not file names. These are URLs. Their goal is to describe the resource. Nobody cares whether you did it in PHP or ASP or typed your HTML in the Emacs. Nobody cares that you named your file index.php. We like to see clean URLs with clear structure and semantics.
I feel dumb for not knowing this, but I see a lot of links in web pages and instead of this:
<a href="http://foo.com/">
...they use this:
<a href="http://foo.com/?src=bar.com">
Now I understand that the ?src= is telling something that this referral is coming from bar.com, but I don't understand why this needs to be called out explicitly. Can anyone shed some light on it for me? Is this something I need to include in my program generated links?
EDIT: Ok, sorry, I'm not being clear enough. I understand the GET syntax with a question mark and parameters separated by ampersands. I'm wondering what's this special src parameter? Why would one site link to another and tack an src parameter on the end even though there's no indication that the destination site uses this normally.
For example, on this page hover your mouse over the screenshot. The link URL is http://moms4mom.com/?src=stackexchangesites
But moms4mom.com is our site. Passing the src parameter does nothing, so why include it?
There are a few reasons that the src is being used explicitly. But in general, it is easier and more reliable to trust a query string to determine referer[sic] than it is to trust the referer, since the latter is often broken, deliberately or not. On the other hand, browsers almost never break the query string in a url, since this, unlike referers, is pretty important for pages to function. Besides, a referer is often done without any deliberate action on the part of the site doing the refering, which some users dislike.
The reason (I do it) is that popular analytics tools sometimes make it easier to filter on query strings than referrers.
There is no standard to the src parameter. Each site has its own and it's usually up to the site that gets the link to define how it wants to read it (as usually it's that site that's going to pay for the click).
The second is a dynamic link, it's a URL that another language(like ASP and PHP) interpret as something to do, like in those Google URLs, but i never used this site(foo.com), then i don't much things about this parameter.
Depending on how the site processes its URL, you may or may not need to include the ?... information.
This is passed to the website, and the server can process it just like form input. Some sites require this - and build their navigation off a single page, using nothing but the "extra" stuff passed afterwards. If you're generating a link to a site like that, it will be required.
In other cases, this is just used to pass extra, unrequired info (such as advertising, tracking info, etc)... In those cases, you can leave it off.
Unfortunately, there's no way to know without trying whether you can remove the "extra" bits from the URL.
After reading some of your comments - I'll also say:
There is nothing special about the "src" field in a query string. The server is free to use it any way it wishes. Unless you know specific info about the server, you cannot assume it can be left out.
The part after the ? is the query string. Different sites use it for different things, and it is usually used for passing information to the server side code for that URL, but can also be used in javascript.
For more info see Query String