Top 10 Basic Linux Fundamentals you should

Linux continues to be the backbone of modern computing, powering everything from servers to smartphones, IoT devices, and even space exploration. Whether you’re a budding developer, system admin, or simply curious about open-source operating systems, mastering Linux fundamentals is a must. Here’s a breakdown of the top 10 basic Linux concepts everyone should understand in 2024.

1. The Command Line Interface (CLI)

The Linux command line, or terminal, is where the real power of Linux lies. While graphical user interfaces (GUIs) are available, the CLI gives you precise control over your system. Commands like ls, cd, cp, and rm help you navigate and manage files. Learning to use the command line efficiently allows for faster task execution and automation.

ls   # List directory contents
cd   # Change directory
mkdir # Make directory
rm   # Remove files or directories

2. File Permissions and Ownership

Understanding how Linux handles file permissions is critical for system security and proper file management. Linux uses three permission levels: read, write, and execute, which apply to three types of users: owner, group, and others. The chmod and chown commands let you change file permissions and ownership.

chmod 755 filename  # Change file permissions
chown user:group filename  # Change file owner

3. Package Management

Linux distributions use package managers to install, update, and remove software. Package managers like apt (for Debian-based systems like Ubuntu) and dnf or yum (for Red Hat-based systems) handle dependencies and ensure that software is up to date.

apt update && apt upgrade  # Update packages (Ubuntu/Debian)
dnf install packagename    # Install a package (Fedora/CentOS)

4. User and Group Management

Linux is a multi-user system. Each user has a unique ID, and users can be grouped for easier permission management. You should know how to create, delete, and modify users and groups using commands like useradd, usermod, and groupadd.

useradd username  # Add a new user
passwd username   # Set or change a password
usermod -aG groupname username  # Add user to group

5. Networking Basics

Linux is widely used in networking, making it crucial to understand basic network configuration and troubleshooting. Familiarity with commands like ifconfig, ip, and ping allows you to configure IP addresses, test connectivity, and troubleshoot network issues.

ifconfig        # View network interfaces (older systems)
ip addr         # View network interfaces (modern systems)
ping google.com # Test network connectivity
netstat -tuln   # Check network status

6. File System Hierarchy

Linux follows a standardized file system hierarchy. Key directories include /home (user files), /var (system logs), /etc (config files), and /usr (user binaries and libraries). Understanding the layout of the file system is essential for managing files and navigating the OS.

Important Directories:

/home – User home directories
/var/log – System logs
/etc – Configuration files

7. Shell Scripting

Learning to write shell scripts allows you to automate repetitive tasks. Shell scripting involves writing scripts in a command language, typically Bash (Bourne Again Shell). These scripts can automate backups, user account creation, and system monitoring.

#!/bin/bash

# Variables
NAME="Linux User"

# Loops
for i in {1..5}; do
  echo "Iteration $i"
done

# Conditionals
if [ -f /path/to/file ]; then
  echo "File exists"
else
  echo "File not found"
fi

8. Process Management

Linux handles running applications and background tasks as processes. Understanding how to view, kill, and manage processes is vital. Tools like top, ps, and kill help you monitor system performance and manage resource-heavy processes.

ps aux      # List running processes
top         # Monitor system resources
kill 1234   # Terminate a process by PID

9. Disk Management

Efficiently managing disk space is essential in Linux. Commands like df and du show disk usage, while partition management tools like fdisk or parted allow you to create, modify, and format partitions.

df -h       # Report disk space usage
du -sh *    # Estimate file and directory space usage
fdisk /dev/sda  # Manage disk partitions

10. System Monitoring and Logs

Linux provides robust tools for monitoring system performance and tracking down issues via logs. top, htop, and free provide insights into CPU, memory, and resource usage, while log files in /var/log contain valuable information for diagnosing problems.

top          # Monitor system resources
htop         # Interactive process viewer
free -h      # Check memory usage
tail -f /var/log/syslog  # View system logs in real time

Mastering these basic Linux fundamentals will equip you to navigate the ever-evolving landscape of open-source computing in 2024. Whether you’re managing a server, automating tasks, or troubleshooting a network, these concepts are your gateway to unlocking the full power of Linux.

Inuar Tech