Page 128 - HTML5

Value/Directive Meaning

nofollow Do not follow the links on this page

follow The links on the page can be followed. See note below.

none Equivalent to noindex, nofollow.

Do not make a cached version of this page available in search
noarchive
results.
nocache Synonym of noarchive used by some bots such as Bing.

nosnippet Do not show a snippet of this page in search results.

Do not use metadata of this page from the Open Directory
noodp
project for titles or snippets in search results.
notranslate Do not offer translations of this page in search results.

noimageindex Do not index images on this page.

Do not show this page in search results after the specified
unavailable_after [RFC-850
date/time. The date/time must be specified in the RFC 850
date/time]
format.
Note: Explicitly defining index and/or follow, while valid values, is not necessary as pretty
much all search engines will assume they are allowed to do so if not explicitly prevented from
doing so. Similar to how the robots.txt file operates, search engines generally only look for
things they are not allowed to do. Only stating things a search engine isn't allowed to do also
prevents accidentally stating opposites (such as index, ..., noindex) which not all search
engines will treat in the same way.

Phone Number Recognition

Mobile platforms like iOS automatically recognize phone numbers and turn them into tel: links.
While the feature is very practical, the system sometimes detects ISBN codes and other numbers
as telephone numbers.

For mobile Safari and some other WebKit-based mobile browsers to turn off automatic phone number
recognition and formatting, you need this meta tag:

<meta name="format-detection" content="telephone=no">

Social Media

Open Graph is a standard for metadata that extends the normal information contained within a
site's head markup. This enables websites such as Facebook to display deeper and richer
information about a website in a structured format. This information is then automatically
displayed when users share links to websites containing OG metadata on Facebook.

Facebook / Open Graph

<meta property="fb:app_id" content="123456789">
<meta property="og:url" content="https://example.com/page.html">
<meta property="og:type" content="website">
<meta property="og:title" content="Content Title">
<meta property="og:image" content="https://example.com/image.jpg">
<meta property="og:description" content="Description Here">
<meta property="og:site_name" content="Site Name">

https://riptutorial.com/ 112