A calendar is a structured number grid for time. To find how many days separate two events, locate both dates, decide which direction time moves, then count the jumps between dates.
Reliable routine: Find start → Find finish → Count jumps → Cross weeks/months carefully → Check.
- A day is Monday, Tuesday and so on.
- A date identifies a particular day in a month, such as 18 March.
- One week later is usually 7 days later and appears in the same weekday column.