Root access refers to the highest level of permission on a computer system, particularly in operating systems like Linux and Unix. It allows a user to have complete control over the system, enabling them to modify system files, install software, and change settings that regular users cannot access. This level of access is essential for system administrators who need to manage and maintain the system effectively. Having root access can also pose security risks. If unauthorized users gain root access, they can compromise the entire system, leading to data loss or corruption. Therefore, it is crucial to protect root access with strong passwords and limit its use to trusted individuals only.