When presenting data you may want to add additional context so anyone viewing your dashboard will have the full picture. Using annotations you can pinpoint exact points on your graphs/charts and add this additional detail to your widget.
On your dashboard click on the graph or chart that you would like to add an annotation to.
This will open up the expanded widget detail panel. Along the top, you will see two tabs. Click the tab titled Annotations.
Once in the annotations tab click + Add Annotation
Select the date you'd like to add an annotation to and then write your comment. This will automatically save and immediately populate on your graph/chart.
This annotation will be visible both on your live dashboards and any snapshots you send. You can read the specific details upon hover.