Open Graph is a small set of invisible tags in a web page's code that tell social platforms, like Facebook and LinkedIn, what to show when someone shares a link to that page. The image, the headline, and the short blurb that appear in a shared post do not come from nowhere; they come from these tags. When you share a link and the preview shows the wrong picture, an old title, or no image at all, that is an Open Graph problem. It is one of those things nobody notices until it looks broken, and then it looks broken to everyone who sees the share. Getting it right is not complicated, but it has to be set deliberately, page by page or through a sensible default, so that every link shared from your site presents the way you intend. On the work I build, Open Graph tags are part of the setup rather than an afterthought, because a link that previews cleanly gets clicked more often than one that previews as a grey box.
Glossary entry