When you first install Kali Linux, the default username and password are both 'root'.

It is highly recommended to change the default password immediately after installation to enhance the security of your system as leaving default credentials can pose a risk of unauthorized access.

Changing the default password in Kali Linux is a straightforward process. Simply open a terminal and type 'passwd', then follow the instructions to set a new password.

Remember to choose a strong and unique password that includes a combination of letters, numbers, and special characters to ensure maximum security.

By changing the default password and practicing good password hygiene, you can significantly reduce the chances of falling victim to cyber attacks.