Tuesday, September 20, 2016

Search Engine Optimization & Website Contents

The world of Seo or Search Engine Optimization is constantly changing. At present the SERPs are unstable as search engine try to perfect their indexing and ranking system. Much to the dismay of webmasters some criteria has been set which gives preference to brands, major chains and even websites that are not optimized at all or those with soddy contents.      

A constant evolution is taking place with regards to the algorithms responsible for placing websites and blogs on search engine result pages or SERPs. 

The SE companies are constantly involved in improving results that would convince visitor of their effectiveness in response to the query.  With the induction of Panda and Penguin most of the spammers have been ousted and optimization has become as tough task.   

Optimization is no longer limited to link building as it was earlier. A vast range of matrix have come into play with various degree of effects. Among the major influences, website contents and authoritative linking plays major roles. Both the elements are related - creating authoritative links requires excellent contents. 

Hence contents become supreme. This means one should have good, relevant and unique contents on websites. Writing for users is a prerequisite but some elements of seo should be present.  Many website owners skip due importance that should be accorded to contents. 

Writing is not only a skill but it is an art too. The first step in content creation is to create a link architecture which elaborates what topics would be present on the website. This begins right at the white board stage.          
The link architecture should be created in a top down manner with the priority pages on the top. While creating the topic list link naming should take place using keyword related to the topic. 

As always, the home page should be written first, it should comprise of summary of what the website is about. This is where tags, title, meta all come into picture. Hence write the contents such that they incorporate major search terms along with semantics. The contents should be neatly divided into readable paragraphs interspersed with relevant images which are properly optimized.     

As per old practice keep the targeted search terms in the first and last paragraph while including semantics within. The contents should be highly relevant and should justify the domain and the title. The domain should be based on related search terms but the ranking algorithms do not rate them as highly as they did before. So a company name or any other name is not a disadvantage...well to some extent.       

Whence writing make sure that there is no duplicity and violation of rights of  others. Hence do not copy contents....do not plagiarize.. and no scraping please this is copyright infringement and search engine are not kind to such write ups.   

Writing unique contents means digging deep using research. If you are writing about less searched topic, it would rank better on the SERPs. This simply means there is less competition, and hence less chance getting buried in a pile of redundant websites which have not been able to climb the ladder. 

So if you are writing about an economy hotel stick to it there is no need to describe a luxury of five star . property. You will be aiming to place your website on budget, cheap, economy hotels not luxury hotels mind you.   

Whence you write on internal pages see that each and every page offer unique but related information. If you find a page has similarity but you still need to keep it onsite then use the "rel=canonical" tag. 

Yes proper grammar and structure as good as they could be should be given top priority. These guidelines also apply for creating contents whence building authoritative links using article, blogs and news. Last but not the least saturate your web pages with good amount of write up optimum being two hundred and fifty words. If it is an eCommerce site  proper product description creates a winning portal.  

Wednesday, September 7, 2016

Social Media : Content Curation?

Content Curation in simple words is aggregation of the best content available online. This can be further paraphrased as  topic related or relevant content that users find useful and entertaining. Naturally it should also be information rich since that is what wildly searched on Net - unique information.  

While in Social Media we try to make our platforms like blogs, article sites, websites and forums rich in content we can not always do it ourselves. Hence in order to fulfill the content gap we usurp that which is available freely on the Internet. This is not plagiarism since the link of the site where it is published in attached to the article.      

Apart from information dissemination and entertainment contents also increase online followers seeking all this. This then becomes an important marketing tool and raise brand equity of businesses.    

If effectively curated the social media platform becomes a one stop shop for those seeking the right stuff. This also helps avoid long and tiring searches on the unfathomable web.   

Sharing content propagated by outsiders in nothing shameful on the contrary it is wise strategy. Content curation increases versatility of what you make available and in a way increases your authority by enhancibg your grasp  of the subject. 

There are many tools on WWW available to sort out, choose and publish outsider contents.    

Monday, September 5, 2016

Social Media: Online Communication & More

With the advent of Internet, a paradigm shift has taken place as to how we communicate. The greatest flip has arisen out of the coming of social media platforms which have - if not of all - heightened thinking, educated, changed the mindset and attitude of the literate class, professionals and amateurs alike.   

Information transformation has been tremendous, accessible to one and all, and may I add cheaply. The versatile social media platforms have proven to be excellent communication channels in terms of written words, audio/video.

Besides being instrumental in networking of like minded, niche set and the common man. They have augured the interests pertaining to various fields/topics, be it business, hobbies, activities and what not. Hence they carry with them endless possibilities of making effective social changes and broadening our spectrum of thoughts and attitude in the right manner. This has been evident by the transformation and upheaval created by the bloggers. Members of forums and groups (online communities) has been able to express views, exploit and disseminate information pertaining to their interests with ease.   

Holistic in approach, Facebook, LinkedIn & Twitter with ample space for communication, tools for creativity along with admixture of entertainment channels have proven to be the most successful online phenomenon.  For propaganda, business and publicity these media tools offer exciting possibilities which are continuously evolving, hence the thunderous success and popularity.

The medium offers endless courting space, thanks to graphic tools, content possibilities and audio for sales conversions, promotions and creating a target audience. There are many niche platforms which  focus on aspects that do not float in a void but are more of hubs with specific offerings.

Not only people, news channels, companies, organizations, NGOs, professionals, career seekers, all have been attracted to the medium. This has proven to be an economic dais that has given them a voice and increased visibility, to paraphrase - a means of expression that is not possible elsewhere without a large man power and expenditure.    

The cyber space is witness to  many startups...platforms that come with promise and vanish overnight, only the deserving survive.  Complex platforms with restrictions or conditional approach have experienced diminished access to audience as compared to the mega portals which have become part of our lives.

What has been so far restricted by the offline or traditional paper based media to specialists, professionals, news mongers, writers and journalists has reached the palms of the ordinary man and his milieu. The collective phenomena with the tremendous possibility of accumulation and dispersal of information online has become an extension or our mind, body and soul.

Albeit free, these platforms offer enhanced accessibility to specialized tools through the paid options. Not bound by boundaries, timings, speed or distance, the phenomena is here to stay.  

Thursday, May 12, 2016

Understanding International Seo - Country Targeting

Like the earlier post this blog entry deals with country targeting oblivious of the language. The Google Console offers a Geo-targeting option which tells the search engine the region in focus.

While focusing on country or a particular language one should also use relevant images and write ups. If the site is aided with a blog than this is a good option to provide related entries.

In both the cases Domain and IP address hold a higher degree of importance. But this may not be the case all the time hence the above factors will be of great help.       

In case of both use the correct language code to identify the language in ISO 639-1 format. And the region in ISO 3166-1 Alpha 2 format of an alternate URL.

For more information read support Google article.  

Understanding International Seo - Language Targeting

Relevancy is the key to search engine optimization brought about by the right contents, right submission process and equally matched by design and functionality. 

The search engine offer relevant answers to queries submitted by the user. This is their job..provide what the users seek.      

In the complex process of indexing and ranking the website is evaluated using hundreds of matrix many of which are not known to webmasters let alone the users. But a common sense approach is what furnishes results to the web owners made possible by webmasters.

In local search the website internal architecture and contents point towards a specific region. Most of the submissions are made in local directories. The site is further aided by the use of meta data and snippets.In this case it is good idea to host the website on local IP provided by the hosting company.  

Some sites tend to be useful to local area as well as larger global audience. If the site is meant for a specific country the language used should be that used by most.  In case of a resource with pages in different languages the alternate tag below is used to inform the search engines. 

<link rel="alternate" href="http://example.com" hreflang="en-us" />   

Not all elements on page are used to augment rankings but the usefulness of the above tag is obvious. These are the element which increase relevancy and usefulness and hence increase conversion. This way one can also reduce bounce rate hence have a positive effect on rankings too.     

Using country specific TLC or domain is the best practice. But on oft occasions this may not be possible hence one can create a sub-domain in order to furnish the user with preferred language.  Creating sub directories and silos are another possible methods. 

If no solution is possible due to resource constraints  than in that case use the translator to help users read contents in language they understand.

Tuesday, March 22, 2016

HTTPS All About It

Ever sine the cat came out of the bag HTTPS protocol has become more popular. There is a ranking benefit in case of using this one. The hyper text transfer protocol is used to transfer data to the browser. This is what makes it possible to download and see website and use the interactive mechanism.     

Like the search engines the users have also become aware of security accorded by this protocol as compared to simple version HTTP. The difference is accentuated by the security certificate associated by intervention of a reputed third party.  

Hence ii offers security through authorized transaction very useful in case of eCommerce stores and payment sites. Overall trust created by this environment attracts more and more converts in the present times.  This protocol is associated with a secured socket layer or SSL sometimes also referred as TLS.    

This technology allows encryption of data that is being exchanged. This also assures that data corruption cannot take place without being discovered.    

But for those sites being transferred to this secured technology it is important that transition takes place in the right manner and does not end up confusing the search engines.  

Earlier Article on HTTPs

AMP HTML Specification

This article has been picked up for readers...due credit is given to the source linked below.  

AMP HTML is a subset of HTML for authoring content pages such as news articles in a way that guarantees certain baseline performance characteristics.

Being a subset of HTML, it puts some restrictions on the full set of tags and functionality available through HTML but it does not require the development of new rendering engines: Existing user agents can render AMP HTML just like all other HTML.

Also, AMP HTML documents can be uploaded to a web server and served just like any other HTML document; no special configuration for the server is necessary. However, they are also designed to be optionally served through specialized AMP serving systems that proxy AMP documents. These documents serve them from their own origin and are allowed to apply transformations to the document that provide additional performance benefits. An incomplete list of optimizations such a serving system might do is:
  • Replace image references with images sized to the viewer’s viewport.
  • Inline images that are visible above the fold.
  • Inline CSS variables.
  • Preload extended components.
  • Minify HTML and CSS.
AMP HTML uses a set of contributed but centrally managed and hosted custom elements to implement advanced functionality such as image galleries that might be found in an AMP HTML document. While it does allow styling the document using custom CSS, it does not allow author written JavaScript beyond what is provided through the custom elements to reach its performance goals.
By using the AMP format, content producers are making the content in AMP files available to be crawled (subject to robots.txt restrictions), cached, and displayed by third parties.

Performance

Predictable performance is a key design goal for AMP HTML. Primarily we are aiming at reducing the time until the content of a page can be consumed / used by the user. In concrete terms this means that:
  • HTTP requests necessary to render and fully layout the document should be minimized.
  • Resources such as images or ads should only be downloaded if they are likely to be seen by the user.
  • Browsers should be able to calculate the space needed by every resource on the page without fetching that resource.

The AMP HTML format

Sample document



<!doctype html>
<html >
  <head>
    <meta charset="utf-8">
    <title>Sample document</title>
    <link rel="canonical" href="./regular-html-version.html">
    <meta name="viewport" content="width=device-width,minimum-scale=1,initial-scale=1">
    <style amp-custom>
      h1 {color: red}
    </style>
    <script type="application/ld+json">
    {
      "@context": "http://schema.org",
      "@type": "NewsArticle",
      "headline": "Article headline",
      "image": [
        "thumbnail1.jpg"
      ],
      "datePublished": "2015-02-05T08:00:00+08:00"
    }
    </script>
    <script async custom-element="amp-carousel" src="https://cdn.ampproject.org/v0/amp-carousel-0.1.js"></script>
    <style amp-boilerplate>body{-webkit-animation:-amp-start 8s steps(1,end) 0s 1 normal both;-moz-animation:-amp-start 8s steps(1,end) 0s 1 normal both;-ms-animation:-amp-start 8s steps(1,end) 0s 1 normal both;animation:-amp-start 8s steps(1,end) 0s 1 normal both}@-webkit-keyframes -amp-start{from{visibility:hidden}to{visibility:visible}}@-moz-keyframes -amp-start{from{visibility:hidden}to{visibility:visible}}@-ms-keyframes -amp-start{from{visibility:hidden}to{visibility:visible}}@-o-keyframes -amp-start{from{visibility:hidden}to{visibility:visible}}@keyframes -amp-start{from{visibility:hidden}to{visibility:visible}}</style><noscript><style amp-boilerplate>body{-webkit-animation:none;-moz-animation:none;-ms-animation:none;animation:none}</style></noscript>
    <script async src="https://cdn.ampproject.org/v0.js"></script>
  </head>
  <body>
    <h1>Sample document</h1>
    <p>
      Some text
      <amp-img src=sample.jpg width=300 height=300></amp-img>
    </p>
    <amp-ad width=300 height=250
        type="a9"
        data-aax_size="300x250"
        data-aax_pubname="test123"
        data-aax_src="302">
    </amp-ad>
  </body>
</html>

Required markup

AMP HTML documents MUST
  • start with the doctype <!doctype html>. 🔗
  • contain a top-level <html > tag (<html amp> is accepted as well). 🔗
  • contain <head> and <body> tags (They are optional in HTML). 🔗
  • contain a <link rel="canonical" href="$SOME_URL" /> tag inside their head that points to the regular HTML version of the AMP HTML document or to itself if no such HTML version exists. 🔗
  • contain a <meta charset="utf-8"> tag as the first child of their head tag. 🔗
  • contain a <meta name="viewport" content="width=device-width,minimum-scale=1"> tag inside their head tag. It’s also recommend to include initial-scale=1 (1). 🔗
  • contain a <script async src="https://cdn.ampproject.org/v0.js"></script> tag inside their head tag. 🔗
  • contain the AMP boilerplate code in their head tag. 🔗
(1) width=device-width,minimum-scale=1 is required to ensure GPU rasterization is enabled.

Metadata

It is encouraged that AMP HTML documents are annotated with standardized metadata: Open Graph Protocol, Twitter Cards, etc.
We also recommend that AMP HTML documents are marked up with schema.org/CreativeWork or any of its more specific types such as schema.org/NewsArticle or schema.org/BlogPosting.

HTML Tags

HTML tags can be used unchanged in AMP HTML. Certain tags have equivalent custom tags (such as <img> and <amp-img>) and other tags are outright prohibited:
Tag Status in AMP HTML
script Prohibited unless the type is application/ld+json. (Other non-executable values may be added as needed.) Exception is the mandatory script tag to load the AMP runtime and the script tags to load extended components.
base Prohibited
img Replaced with amp-img.
video Replaced with amp-video.
audio Replaced with amp-audio.
iframe Replaced with amp-iframe.
frame Prohibited.
frameset Prohibited.
object Prohibited.
param Prohibited.
applet Prohibited.
embed Prohibited.
form Prohibited. Support coming in the future.
input elements Prohibited. Includes input, textarea, select, option. Notably, button element is allowed.
button Allowed.
style Required style tags for adjusting opacity. One additional style tag is allowed in head tag for the purpose of custom styling. This style tag must have the attribute amp-custom. [🔗](https://github.com/ampproject/amphtml/blob/master/spec/#cust)
link rel values registered on microformats.org are allowed. If a rel value is missing from our whitelist, please submit an issue. stylesheet and other values like preconnect, prerender and prefectch that has side effects in the browser are disallowed. There is a special case for fetching stylesheets from whitelisted font providers.
meta The http-equiv attribute is banned. Otherwise allowed.
a The href attribute value must not begin with javascript:. If set, the target attribute value must be _blank. Otherwise allowed. [🔗](https://github.com/ampproject/amphtml/blob/master/spec/#ancr)
svg Most SVG elements are allowed.
Validator implementations should use a whitelist based on the HTML5 specification with the above tags removed. See AMP Tag Addendum.

Comments

Conditional HTML comments are not allowed.

HTML attributes

Attribute names starting with on (such as onclick or onmouseover) are disallowed in AMP HTML. The attribute with the literal name on (no suffix) is allowed.
The style attribute must not be used.
XML-related attributes, such as xmlns, xml:lang, xml:base, and xml:space are disallowed in AMP HTML.
The javascript: schema is disallowed.

Stylesheets

Major semantic tags and the AMP custom elements come with default styles to make authoring a responsive document reasonably easy. An option to opt out of default styles may be added in the future.

@-rules

The following @-rules are allowed in stylesheets:
@font-face, @keyframes, @media, @supports.
@import will not be allowed. Others may be added in the future.

Author stylesheets

Authors may add custom styles to a document using a single <style amp-custom> tag in the head of the document.

Selectors

The following restrictions apply to selectors in author style sheets:
Universal selector
The universal selector * may not be used in author stylesheets. This is because it can have negative performance implications and could be used to circumvent the rules set out in the following paragraph.
not selector
:not() may not be used in selectors because it can be used to simulate the universal selector.
Pseudo-selectors, pseudo-classes and pseudo-elements
Pseudo-selectors, pseudo-classes and pseudo-elements are only allowed in selectors that contain tag names and those tag names must not start with amp-.
Example OK: a:hover, div:last-of-type
Example not OK: amp-img:hover, amp-img:last-of-type
Class and tag names
Class names, in author stylesheets, may not start with the string -amp-. These are reserved for internal use by the AMP runtime. It follows, that the user’s stylesheet may not reference CSS selectors for -amp- classes and i-amp tags. These classes and elements are not meant to be customized by authors. Authors, however, can override styles of amp- classes and tags for any CSS properties not explicitly forbidden by these components’ spec.
To prevent usage of attribute selectors to circumvent class name limitations it is generally not allowed for CSS selectors to contain tokens and strings starting with -amp- and i-amp.

Important

Usage of the !important qualifier is not allowed. This is a necessary requirement to enable AMP to enforce its element sizing invariants.

Properties

These CSS properties are permanently banned:
  • behavior
  • -moz-binding
The following properties are currently blacklisted due to performance concerns:
  • filter
AMP only allows transitions and animations of properties that can be GPU accelerated in common browsers. We currently whitelist: opacity, transform (also -vendorPrefix-transform).
In the following examples <property> needs to be in the whitelist above.
  • transition <property> (Also -vendorPrefix-transition)
  • @keyframes name { from: {<property>: value} to {<property: value>} } (also @-vendorPrefix-keyframes)
overflow (and overflow-y, overflow-x) may not be styled as “auto” or “scroll”. No user defined element in an AMP document may have a scrollbar.
Maximum size
It is a validation error if the author stylesheet is larger than 50,000 bytes.

Custom fonts

Authors may include stylesheets for custom fonts. The 2 supported methods are link tags pointing to whitelisted font providers and @font-face inclusion.
Example:


<link rel="stylesheet" href="https://fonts.googleapis.com/css?family=Tangerine">
Font providers can be whitelisted if they support CSS-only integrations and serve over HTTPS. The following origins are currently allowed for font serving via link tags:
  • https://fast.fonts.net
  • https://fonts.googleapis.com
IMPLEMENTERS NOTE: Adding to this list requires a change to the Google AMP Cache CSP rule.
Authors are free to include all custom fonts via a @font-face CSS instruction via their custom CSS. Fonts included via @font-face must be fetched via the HTTP or HTTPS scheme.

AMP runtime

The AMP runtime is a piece of JavaScript that runs inside every AMP document. It provides implementations for AMP custom elements, manages resource loading and prioritization and optionally includes a runtime validator for AMP HTML for use during development.
The AMP runtime is loaded via the mandatory <script src="https://cdn.ampproject.org/v0.js"></script> tag in the AMP document <head>.
The AMP runtime can be placed into a development mode for any page. Development mode will trigger AMP validation on the embedded page, which will emit the validation status and any errors to the javascript developer console. Development mode may be triggered by appending #development=1 to the URL of the page.

Resources

Resources such as images, videos, audio files or ads must be included into an AMP HTML file through custom elements such as <amp-img>. We call them managed resources because whether and when they will be loaded and displayed to the user is decided by the AMP runtime.
There are no particular guarantees as to the loading behavior of the AMP runtime, but it should generally strive to load resources quickly enough, so that they are loaded by the time the user would like to see them if possible. The runtime should prioritize resources currently in viewport and attempt to predict changes to the viewport and preload resources accordingly.
The AMP runtime may at any time decide to unload resources that are not currently in viewport or reuse the resource containers such as iframes to reduce overall RAM consumption.

AMP Components

AMP HTML uses custom elements called, “AMP components” to substitute built-in resource-loading tags such as <img> and <video> and to implement features with complex interactions such as image lightboxes or carousels.
See the AMP component spec for details about supported components.
There are 2 types of supported AMP components:
  1. Built-in
  2. Extended
Built-in components are always available in an AMP document and have a dedicated custom element such as <amp-img>. Extended components must be explicitly included into the document.

Common attributes

layout, width, height, media, placeholder, fallback

These attributes define the layout of an element. The key goal here is to ensure that the element can be displayed and its space can be properly reserved before any of the JavaScript or remote resources have been downloaded.
See the AMP Layout System for details about the layout system.

on

The on attribute is used to install event handlers on elements. The events that are supported depend on the element.
The value for the syntax is a simple domain specific language of the form:


eventName:targetId[.methodName[(arg1=value, arg2=value)]]
Example: on="tap:fooId.showLightbox"
If methodName is omitted the default method is executed if defined for the element. Example: on="tap:fooId"
Some actions, if documented, may accept arguments. The arguments defined in the parenthesis in the key=value notation. The accepted values are:
  • simple unquoted strings: simple-value;
  • quoted strings: "string value" or 'string value';
  • boolean values: true or false;
  • numbers: 11 or 1.1.

Extended components

Extended components are components that do not necessarily ship with the AMP runtime. Instead they must be explicitly included into the document.
Extended components are loaded by including a <script> tag in the head of the document like this:


<script async custom-element="amp-carousel" src="https://cdn.ampproject.org/v0/amp-carousel-0.1.js"></script>
The <script> tag must have an async attribute and must have a custom-element attribute referencing the name of the element.
Runtime implementations may use the name to render placeholders for these elements.
The script URL must start with “https://cdn.ampproject.org” and must follow a very strict pattern of /v\d+/[a-z-]+-(latest|\d+|\d+.\d+).js.
URL
The URL for extended components is of the form:


https://cdn.ampproject.org/$RUNTIME_VERSION/$ELEMENT_NAME-$ELEMENT_VERSION.js

Versioning
Extended components are versioned via semver. The version is referenced explicitly (See $ELEMENT_VERSION above) when loading the component in the URL. It may have the value “latest”. Changes to the PATCH version component (x in 1.1.x) must strictly maintain backward compatibility or fix urgent security issues.
AMP documents may only reference versions with one or two components. Version “1” states “I accept every version of this component with major version 1”. Version “1.1” states “I accept every PATCH level of 1.1”. It is now allowed to explicitly reference the PATCH level in the version string.

Extended templates

Templates render HTML content based on the language-specific template and provided JSON data.
See the AMP template spec for details about supported templates.
Extended templates are not shipped with the AMP runtime and have to be downloaded just as with extended elements. Extended components are loaded by including a <script> tag in the head of the document like this:


<script async custom-template="amp-mustache" src="https://cdn.ampproject.org/v0/amp-mustache-0.1.js"></script>
The <script> tag must have an async attribute and must have a custom-template attribute referencing the type of the template. The script URL must start with “https://cdn.ampproject.org” and must follow a very strict pattern of /v\d+/[a-z-]+-(latest|\d+|\d+.\d+).js.
The templates are declared in the document as following:


<template type="amp-mustache" id="template1">
  Hello !
</template>
The type attribute is required and must reference a declared custom-element script.
The id attribute is optional. Individual AMP elements discover their own templates. Typical scenario would involve an AMP element looking for a <template> either among its children or referenced by ID.
The syntax within the template element depends on the specific template language. However, the template language could be restricted within AMP. For instance, in accordance with the “template” element, all productions have to be over a valid well-formed DOM. All of the template outputs are also subject to sanitizing to ensure AMP-valid output.
See documentation for a specific extended template on the syntax and restrictions.
URL
The URL for extended components is of the form:


https://cdn.ampproject.org/$RUNTIME_VERSION/$TEMPLATE_TYPE-$TEMPLATE_VERSION.js

Versioning
See versioning of custom elements for more details.

Security

AMP HTML documents must not trigger errors when served with a Content Security Policy that does not include the keywords unsafe-inline and unsafe-eval.
The AMP HTML format is designed so that is always the case.
All AMP template elements must go through AMP security review before they can be submitted into AMP repository.

SVG

Currently, the following SVG elements are allowed:
  • basics: “svg”, “g”, “path”, “glyph”, “glyphRef”, “marker”, “view”
  • shapes: “circle”, “line”, “polygon”, “polyline”, “rect”
  • text: “text”, “textPath”, “tref”, “tspan”
  • rendering: “clipPath”, “filter”, “linearGradient”, “radialGradient”, “mask”, “pattern”, “vkern”, “hkern”
  • special: “defs” (all children above are allowed here), “symbol”, “use”
  • aria: “desc”, “title”
As well as these attributes:
  • “xlink:href”: only URIs starting with “#” are allowed
  • “style”

AMP document discovery

If AMP documents are alternative representations of a canonical document, then the canonical document should point to the AMP document via a link tag with the relation “amphtml”.
Example:


<link rel="amphtml" href="https://www.example.com/url/to/amp/document.html">
The AMP document itself is expected to point back with its canonical relation to a document that has the “amphtml” relation.
Note, that AMP document may also be linked to directly. The mechanism described here provides a standardized way for software to discover whether an AMP version exists for a canonical document.

Source: AMP HTML Specification