almalino OpenGraph is a basically a meta tag standard used for the purposes of bots and services. As an example when you go to twitter, facebook, pintrest, etc. and you see a link that has an image, title, description, etc. already that is because those websites parsed the OpenGraph data and is displaying that to users in a "Rich" format.
The OpenGraph standards are on https://ogp.me/
As an example flarum.org has the follow OpenGraph data:
<meta property="og:type" content="website">
<meta property="og:url" content="https://flarum.org/">
<meta property="og:title" content="Flarum">
<meta property="og:description" content="Flarum is the next-generation forum software that makes online discussion fun. It's simple, fast, and free.">
<meta property="og:image" content="https://flarum.org/assets/img/flarum-banner.png">
There is also another format called Schema that allows for much more information and is used by things like search engines to display those Info panes https://schema.org/docs/schemas.html
As an example flarum.org has the following Schema attached for search engines to parse:
<script type="application/ld+json">
{
"@context": "https://schema.org",
"@type": "NGO",
"name": "Flarum",
"url": "https://flarum.org",
"logo": "https://flarum.org/assets/img/logo.png",
"alternateName": "Flarum Foundation",
"sameAs": [
"https://github.com/flarum",
"https://twitter.com/flarum"
],
"contactPoint": [{
"@type": "ContactPoint",
"contactType": "sales",
"email": "info@flarum.org",
"availableLanguage": [
"en",
"nl",
"fr"
]
}]
}
</script>