You might have come across some websites that when shared on social media platforms like Twitter & WhatsApp shows a preview card of the website which typically includes an image and a short description of the page. This is accomplished with the use of OpenGraph protocol. This is used to add meta data to your websites.
How to add social media preview
This is done by adding OpenGraph meta tags to the <head>
tag of the HTML file. For example:
<!DOCTYPE html>
<html lang="en">
<head>
<title>Page Title</title>
<meta name="description" content="This is the description of the site.">
<meta property="og:url" content="url">
<meta property="og:title" content="Page Title">
<meta property="og:type" content="website">
<meta property="og:image" content="image url">
<meta property="og:url" content="url">
<meta property="og:description" content="This is the description of the site.">
</head>
<body>
</body>
</html>
Some basic OpenGraph properties
og:title
<meta property="og:title" content="Page Title">
This is used to add title, usually the same as the title of the page in <title>
tag.
og:type
<meta property="og:type" content="website">
This is used to add information about what type of page the URL is for. It can be website, article or video.
og:image
<meta property="og:image" content="img_address">
This is used to add image to the preview by adding the image URL.
og:url
<meta property="og:url" content="url">
This property contains the URL of the current page.
Other
There are various other open graph properties like og:description, og:domain, etc. Also there are some special platform specific properties like in the case of twitter.
twitter:card
<meta name="twitter:card" content="summary_large_image">
This gives a large image with summary when the website url is shared on twitter.
Easier way
You can use websites like opengraph.xyz to generate open graph meta tags for your website and customise it.
How to check
You can check if your site's opengrah tags are working on sites like twitter card validator & Facebook sharing debugger
For detailed documentation refer to ogp.me .