A kernel memory dump is a file that captures the contents of a computer's memory at the time of a system crash or failure. This type of dump is useful for diagnosing problems, as it provides a snapshot of the operating system's kernel and running processes, helping developers and system administrators identify the cause of the crash. When a system experiences a critical error, the operating system can create a kernel memory dump to preserve important data. This dump can be analyzed using debugging tools, allowing experts to investigate issues related to hardware, drivers, or software, ultimately improving system stability and performance.