Shell Script - Command Line notation syntax - (feat MS)

Notation	Description
Text without brackets or braces	Items you must type as shown.
<Text inside angle brackets>	Placeholder for which you must supply a value.
[Text inside square brackets]	Optional items.
{Text inside braces}	Set of required items. You must choose one.
Vertical bar |	Separator for mutually exclusive items. You must choose one.
Ellipsis …	Items that can be repeated and used multiple times.

Reference

https://docs.microsoft.com/en-us/windows-server/administration/windows-commands/command-line-syntax-key