Doc
A doc allows a nudge step to feature a document from a synced source. A common class of nudge will surface up a useful document to a user when they might be in need of its contents. For example, a nudge that triggers based on user confusion could surface up an article that explains the page they are on.
Clicking on the thumbnail image will take the user to that doc in HelpHub (to avoid kicing them out to a new tab).