Linux Structure#

What is Linux?#

• An Operating System (OS) like Windows or macOS.
• Man ages hardware and software communication.
• Known for security, performance, and open-source nature.
• Comes in many versions called distributions (distros) like Ubuntu, Fedora, Parrot OS, etc.

History of linux#

Originated from Unix (1970) by Ken Thompson & Dennis Ritchie.

GNU Project (1983) by Richard Stallman aimed to make free OS.

Linux Kernel created in 1991 by Linus Torvalds.

• Now over 600+ distros exist.
• Android is based on the Linux kernel.
• It’s widely used in servers, desktops, routers, phones, etc.

Linux Philosophy#

• Everything is a file – Even settings are stored in text files.
• Small, single-purpose programs – Tools do one thing well.
• Programs work together – Combine tools for complex tasks.
• Avoid GUIs – More power via command line (shell).
• Store config in text files – Easy to edit, e.g., /etc/passwd.

Key Components#

Linux Architecture (Layers)#

• Hardware – Physical parts (CPU, RAM, etc.).
• Kernel – Controls hardware, manages processes.
• Shell – Interface to run commands.
• System Utilities – Tools and programs for users.

File System Hierarchy#