Why Linux Dominates Servers: A Beginner’s Guide to the OS, Filesystem, and Command Line

What is Linux?

Linux is a Unix‑like operating system that manages hardware and software resources. It powers servers, supercomputers, embedded devices, and many desktop environments.

Why is Linux popular?

Free and open‑source: the source code can be viewed, modified, and redistributed without licensing fees.

Highly flexible: runs on routers, IoT devices, smartphones, desktops, and large‑scale clusters. The system can be customized for specific hardware or workload requirements.

Unix philosophy

Linux follows the classic Unix design principles: programs are simple, modular, and composable. Most functionality is exposed as files, allowing small tools to be combined into complex workflows.

Filesystem hierarchy

The Linux filesystem is a single tree rooted at /. Key directories: /bin – essential binaries needed for boot and basic commands. /boot – kernel image and bootloader files. /dev – device node files for hardware interaction. /etc – system‑wide configuration files. /home – personal directories for each user. /lib – shared libraries required by programs. /proc – virtual files exposing kernel and process information. /tmp – temporary files created by programs. /usr – secondary read‑only hierarchy for user‑level software. /var – variable data such as logs, caches, and spool files.

Run man hier to view the complete manual page for the directory layout.

Command‑line basics

The shell (commonly Bash on Linux) interprets textual commands entered in a terminal. Commands generally follow the pattern:

program_name [--optional flags] [optional arguments]

Flags (e.g., -f or --help) modify behavior; arguments are typically file names, strings, or numbers. Paths may be absolute (starting with /) or relative (using . for the current directory and .. for the parent).

Common commands

pwd

– prints the current working directory. cd <path> – changes the current directory; cd without arguments returns to the home directory ( ~). ls – lists directory contents; -a shows hidden files (names beginning with a dot). mv <source> <destination> – moves or renames files and directories. cp <source> <destination> – copies files; -r copies directories recursively. mkdir -p <path> – creates a directory and any missing parent directories. touch <filename> – creates an empty file or updates its timestamp.

Example usage:

ls -a ~/Documents

mv fun-letter.txt hilarious-letter.txt

mkdir -p code/web-stuff/html notes

File operations

Moving or renaming files: mv fun-letter.txt ~/Documents/letters/ Copying files (recursive for directories): cp -r source_dir/ destination_dir/ Creating directories with intermediate parents: mkdir -p project/src include Creating an empty file:

touch README.md

Typical Linux distributions

Popular desktop and server distributions such as Ubuntu, Linux Mint, and Fedora provide ready‑to‑use environments, extensive package repositories, and active community support.

Original article: https://dev.to/emtes/so-linux-3i9k