Timecard enables the possibility of self adding/editing absences without going through all authorization levels.
In timecard you can:
Add / modify absences for current day, the functionality being available only with ESS license and Self Edit Absences permission;
Add / modify absences for multiple days, the functionality being available only with ESS license and Self Edit Absences permission.For this you should set in Configuration - System - Application config. the maximum days for self edit bookings / absences for the past and future.
For more details, see System Settings related to number of days in the past / future to edit absences.