Linux and Kernels Explained

Some definitions I asked my professor to clarify the general ideas of Linux and kernels in my Development Technologies Linux course:

1. Linux: Linux is an operating system, like Windows and MacOS.  It runs on hardware – a laptop, desktop or server (or VM).  Shell is an interface to the system.  Just like a Windows or Mac GUI is an interface to those systems.  Mac has a shell interface as well, and you use the terminal application to interface with it in an interactive way.  When you write a script, you interface with it in an automatic way.  Mac also has ls, grep, sudo.  They are system commands or tools, to get things done.
2. Kernel: Sometimes we talk about Linux being a kernel.  A kernel is a small part of the operating system that runs and managers the hardware.  You don’t see it and don’t necessarily interact with it.  You use commands like ls instead.  In the context where Linux is a kernel, then the system is called GNU/Linux.  This is because the GNU project wrote a lot of the actual operating system, like commands (ls, grep, etc.), compiler, linker, and so on.  You can check it out at gnu.org.

Side notes about organizaing on VM: You can organize your homeworks and assignments in separate directories on your VM, it is good practice to be organized.  It will help you in the future with your projects.