tangming is not in the sudoers file. This incident will be reported.

The phrase "Tangming is not in the sudoers file. This incident will be reported" is a warning message typically encountered in Linux or Unix-based systems when someone tries to use the `sudo` command, which allows a user to execute commands with elevated privileges, but the user "Tangming" is not listed in the system's `sudoers` configuration file. The `sudoers` file specifies which users are authorized to use `sudo`.

This incident is significant because attempting to use sudo without proper permissions is usually a security breach. If the system logs the attempt, it means that there may be an unauthorized attempt to escalate privileges, and this could potentially lead to unauthorized access or actions on the system. As a result, such attempts are often recorded to track security events and to ensure accountability.