Why this Blog?
Why not? I never found decent tutorials or at least explanations of linux, might as well make one and get a boost from it.
What is Linux
Linux is a type of operating system just like Windows and Mac. Linus Torvalds came up with it.
But here's the thing when people say "Linux," they're usually talking about the kernel, which is just one piece of the puzzle. Let me break it down the way I wish someone broke it down for me.
The Kernel - The Brain That Talks to Hardware
Think of the kernel as the middleman between your software and your actual hardware (CPU, RAM, disk, etc.). It's the chunk of code that knows how to:
- Manage memory (who gets what slice of RAM)
- Schedule processes (which program gets CPU time and when)
- Handle device drivers (talking to your keyboard, network card, etc.)
- Manage file systems (how your files actually live on disk)
You never interact with the kernel directly. You don't open it, you don't click on it. It's just there, running underneath everything, making sure your hardware and software play nice together.
Linus Torvalds wrote the Linux kernel. That's literally what "Linux" is, just the kernel. Everything else (the desktop, the terminal, the file manager) is stuff built on top of it.
The Shell - Your Way of Talking to the Kernel
So if the kernel is the brain that talks to hardware... how do you talk to the kernel?
That's the shell.
The shell is a program that takes your commands (typed text) and translates them into something the kernel can act on. It's your interface to the system.
When you open a terminal and type ls to list files, here's what's actually happening:
- You type
lsinto the shell - The shell interprets that and makes a system call to the kernel
- The kernel talks to the file system on your disk
- Results come back up the chain and get printed on your screen
The most common shell you'll run into is Bash (Bourne Again Shell), but there's also Zsh, Fish, and others. They all do the same fundamental job, they're just different flavors of translator between you and the kernel.
Quick Analogy
| Layer | What it is | Analogy |
|---|---|---|
| You | The user | You at a restaurant |
| Shell | Command interpreter | The waiter taking your order |
| Kernel | Core of the OS | The kitchen making your food |
| Hardware | Physical components | The actual ingredients and stove |
That's the foundation. Everything else in Linux (commands, permissions, file systems, processes) builds on top of this relationship between you, the shell, and the kernel.