Quick answer
The Calendar is your month-by-month view of who is off. Today is highlighted in blue, booked leave shows as a bar in that person's colour, bank holidays carry a BH tag, and a stats banner sums up the month.
Find it under
What you are looking at
Use the arrows to move between months, or Today to jump back. The banner across the top totals people off, days booked and team size for the month.

Reading a day
Today’s date is blue. A solid bar in someone's colour is approved leave; an amber bar with an outline dot is still pending. A half day shows an AM or PM tag, a bank holiday shows BH, and birthdays appear with a cake icon. Click any day to view, book or cancel leave.