1. Kernel: The core component of an operating system that manages system resources and enables communication between hardware and software.

2.Linux: Linux is a kernel, but the term is often used to refer to the entire operating system built around the Linux kernel.

3.Linux and Malware: While no OS is completely immune, Linux is generally considered more secure due to its robust permissions model, active open-source community, and limited market share. However, users should still practice good security habits and take precautions to minimize risks.