To diplay todays date:

Markup Text
Displayed as
Today is !today. Today is 24 May, 2018.
XML is !today -xml. XML is 2018-05-24T13:30:38.
Right now it is !today -t. Right now it is 24 May, 2018 13:30.
Tomorrow is !today +1. Tomorrow is 25 May, 2018.
Last week was !today -7. Last week was 17 May, 2018.
The month is !today (MMM). The month is May.

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.)