In cybersecurity, a 'reboot' refers to the process of restarting a computer, device, or system. This action shuts down all running processes and reloads the operating system, often used to resolve software glitches, apply updates, or restore normal operations after a security incident. Rebooting can help clear temporary files, reset network connections, and remove certain types of malware from memory. However, it is not a guaranteed method for eliminating persistent threats, as some malware can survive reboots by embedding themselves deeper into the system. Regular reboots are also recommended as part of routine maintenance to ensure optimal device performance and security.