It seems like you're referring to a keyboard shortcut!

`Ctrl + Shift + O` is a keyboard shortcut commonly used in various applications, including:

1、Google Chrome: This shortcut is used to open a new bookmark or favorite in a new tab.
2、Microsoft Outlook: This shortcut is used to open a new email or message (depending on the context).
3、Other applications: In some other applications, such as Eclipse or IntelliJ IDEA, this shortcut is used to open a file or outline (a list of open files or a file navigator).

Could you please provide more context or clarify which application or system you're referring to? I'd be happy to provide more specific information!