Lesson 1 / 31
Linux Introduction
Learn what Linux is, how the kernel differs from distributions such as Ubuntu and Fedora, and the everything-is-a-file idea.
What is Linux?
Linux is a free, open-source kernel originally created by Linus Torvalds in 1991. Combined with system tools and a package manager, it forms a complete operating system that powers servers, phones (Android), and supercomputers.
Distros at a glance
A distribution (distro) bundles the Linux kernel with software and a package manager. Ubuntu/Debian are beginner-friendly and use apt. Fedora/RHEL/CentOS favor dnf/yum. Arch is minimal and rolling-release.
Everything is a file
A core Linux philosophy: devices, processes, even network sockets are represented as files under /dev, /proc, and /sys. This uniformity is why so many tools compose well together.