GNU/Linux Basics: Kernel, Distros & Install
GNU/Linux Basics: Kernel, Distros & Install
This page introduces GNU/Linux as a major Unix-like operating system, explains its structure, and provides a basic overview of installation.
Kernel vs userland
Linux is technically only the kernel, which manages CPU, memory, and I/O resources. The GNU project provides essential tools such as compilers, libraries, and shells. Together they form the GNU/Linux operating system.
The kernel is separated from user space. Programs run in user space and must use system calls to request services from the kernel.
Distributions
GNU/Linux is packaged into distributions that combine the kernel, GNU tools, and additional software. Examples include Debian, Ubuntu, Fedora, CentOS, Arch, and Gentoo.
Distributions differ in package management systems, release cycles, and intended use cases. Linux dominates in servers, supercomputers, and smartphones (Android), while adoption on desktops remains smaller.
Installing GNU/Linux
The typical installation process is:
- Download an installer image (ISO).
- Write it to a USB stick or boot it in a virtual machine.
- Follow the guided installer to configure language, keyboard, users, and partitions.
The root account has unrestricted control of the system, similar to an administrator in Windows. Normal users operate with limited permissions, increasing security. Many distributions use the sudo command to grant temporary administrative rights.