The Includes Time setting configures a Date/Time component to prompt for date, time, and time zone, or just a date.

No

When set to No, the agent is prompted to select a date only. When clicked, a popover calendar of dates appears for the agent to choose from.

Figures shows control prompting for a date only.
Yes

When set to Yes, the agent is prompted to select a date, time, and time zone.

Figure shows date input control with prompts for date, time, and time zone.

Tip: When setting a callback time, the agent should select the time zone of the contact.