Note: Metrics shown in this section are derived from post level lifetime values for content posted within the selected period.
Likes: Total likes including likes on shares.
Comments: Total comments including comments on shares.
Shares: Total shares including shares on shares.
Impressions: The total number of times users saw your posts.
Interactions: The total number of likes, comments and shares (including interactions received on shares).
Engagement: The total number of times people likes, commented, shared or clicked on your posts.
For more information on Facebook metrics, please refer to the following FB developer resource: https://developers.facebook.com/docs/graph-api/reference/v2.8/insights