What are Annotations in Google Analytics?

Annotations in Google Analytics enable anyone to either comment or even add notes referring to specific dates and events. It also enables marking of specific dates on Google Analytics. Annotations on the interface have many customised privacy options like the choice between note to the public or shared with all the users of Google Analytics or just with you.  Every annotation has a limit of 160. Major uses of annotations are as follows:

• It helps users to remember important events on specific dates which impact data.
• It gives context to all reported data without any external data.
• Wipes the gap between one’s website and the offline events.
• Also, help in finding out which events ultimately impact the website performance.

There are many events which one can mark in Google Analytics using annotations like starting and ending dates of a campaign, launch dates of new products, social networking updates etc.