To diplay todays date:

Markup Text
Displayed as
Today is !today. Today is 22 Sep, 2017.
XML is !today -xml. XML is 2017-09-22T00:45:50.
Right now it is !today -t. Right now it is 22 Sep, 2017 00:45.
Tomorrow is !today +1. Tomorrow is 23 Sep, 2017.
Last week was !today -7. Last week was 15 Sep, 2017.
The month is !today (MMM). The month is Sep.

As you can see, you can add or subtract days. You can include the time tiwh -t. And you can use your own format for the time. (See SimpleDataFormat for the syntax.)