The Date Selection pop up is displayed when you click
the
Date button
that is located next to date fields in the selection pane. It allows you
to quickly lookup a date and transfer it into the date field.

The current day is highlighted in a different color and a larger font.
The day, month, and year can be individually selected. To select the month and year use the Month and Year drop down menus. To select a particular day of the month, click the appropriate day box.
The selected day will be displayed in a larger font.
Click the Apply button to enter the date in the date field.