Microsoft has the following page if you have always wondered what the different symbols and formatting mean when viewing syntax examples.
Transact-SQL Syntax Conventions (Transact-SQL) – SQL Server | Microsoft Docs
It’s always a good exercise to review the DDL statements below and take stock of which options you understand or need to brush up on to become a more skilled developer.

Happy Coding!
Good stuff, Scott. Microsoft threw you a curve. Please update your link to end with “ver16”.