Metadta

Metadata is data about the data.

In the context of social media, while data is the content that is created by a particular user, metadata provides further context about that data.

Let's take a post for example.

A post could have simply been plain text. That is the data.

But metadata is data about the data. And those metadata could be the account handle of the original author. It could be the date and time when the post was created. It could be the comments associated with the post.