Secure Boot is a security feature found in modern computer systems that ensures only trusted software is loaded during the startup process. It works by checking the digital signatures of the operating system and other boot components against a list of approved signatures stored in the system's firmware. If the signatures match, the system proceeds to boot; if not, it prevents the system from starting, helping to protect against malware and unauthorized software. This feature is part of the Unified Extensible Firmware Interface (UEFI), which has largely replaced the older BIOS system. By enforcing a secure boot process, users can have greater confidence that their devices are starting with legitimate software, reducing the risk of attacks that exploit vulnerabilities during the boot phase.