A general-purpose CPU is the main processor in a computer. It executes ordinary program instructions, including arithmetic, control flow, and operations that coordinate software and hardware. Unlike a specialized processor, it is designed to handle many different kinds of tasks.
In cyber security, the CPU runs operating systems, applications, and security tools, so its behavior affects how attacks and defenses operate. Malware can execute instructions on the CPU, while endpoint protection software uses it to inspect activity and enforce rules. Specialized units, such as a floating-point coprocessor, can take over particular operations, but the general-purpose CPU remains responsible for broader software execution.