I’m always trying to remember the different date formats when using the Shortcuts app. Apple has some of the basics on the Shortcuts help page but it doesn’t look into all the options. I’m not a programmer so much this language was foreign to me so I went ahead and took the time to outline what each option looks like as a reference.
If you would like, you can download a text file of this information with Markdown formatting or download the shortcut, which produced this information.
Note: Each of these can be customized with different combinations but at the most basic level M = Month, d = Day, y = Year