The admin has the ability to control the calendar. The calendar allows you to:
Schedule callbacks for a lead
Setup appointments
Add notes
Send reminders by email 10 minutes before an appointment
Send reminders by text 10 minutes before an appointment (feature must be setup)
Add an item to the calendar shows the date you want to setup a reminder, the time, the title, and the description. Then, the notes/reminders will be shown in the manage calendar items section.
MANAGE CALENDAR - Allows you to add an item to the calendar.