The "Messaging" section of the Event Dashboard allows for a quick and easy way to contact to all ticket purchasers, RSVP'd attendees, and event staff.
This is useful for announcing a time or line-up change, notifying attendees about parking availability or a special experience during the event, or offering a discount code for the next event to all who attended this one. (Click here for more info about discount and promo codes)
Hover over "Interact" in the dropdown menu and click on "Messaging".
This will open an email template with a wide range of options to send messages out to different segments of event attendees and even your event staff. Edit the subject, drop the necessary info into the Rich Text box (photos, links...etc), click the send button, and its off!