fdisk Cheatsheet

Quick reference for fdisk commands: list disks, create partition tables, add partitions, change partition types, write changes, and quit safely

How to Install Apache on Ubuntu 26.04

This tutorial will guide you through the process of installing and managing the Apache web server on Ubuntu 26.04. You will learn how to install Apache, open HTTP and HTTPS ports in the firewall, and set up virtual hosts.

What every dev should know about AI sandboxes

An important primitive for the new "AI agent era"

sha256sum and md5sum Commands: Verify File Integrity in Linux

How to use sha256sum and md5sum to generate and verify checksums for files, validate ISO downloads, and detect tampering on Linux systems.

ufw Command in Linux: Uncomplicated Firewall Reference

Reference for the ufw command on Linux, with examples for enabling the firewall, allowing and denying traffic, deleting rules, and managing application profiles.

nslookup Cheatsheet

Quick reference for querying DNS records and checking name resolution with nslookup

lsof Cheatsheet

Quick reference for finding open files, processes, ports, and deleted files with lsof in Linux

Shell Tricks That Actually Make Life Easier (And Save Your Sanity)

Watch someone backspace 40 characters instead of pressing CTRL+W, and you’ll understand why this list exists. A collection of shell tricks-grouped by what works everywhere and what’s Bash/Zsh-speci...

apt vs apt-get: What Is the Difference?

Understand the difference between apt and apt-get in Debian and Ubuntu. When to use each tool, how the commands map to each other, and which one belongs in your scripts.

comm: working with sets and multisets at the command line

The comm utility lets you find which lines are unique to one file or another, and which lines are common to both.

How to Create a systemd Service File in Linux

Create a systemd service file in Linux with step-by-step instructions for unit file structure, service types, restart policies, and service management with systemctl.

su Cheatsheet

Quick reference for switching users and running commands with su in Linux

xargs Cheatsheet

Quick reference for building commands from standard input with xargs in Linux

less Cheatsheet

Quick reference for navigating, searching, and controlling output with the less pager in Linux

journalctl Command in Linux: Query and Filter System Logs

journalctl queries the systemd journal and lets you filter logs by unit, time, priority, boot, and process. This guide covers the most useful journalctl options with practical examples.

Understanding the /etc/fstab File in Linux

The /etc/fstab file defines how filesystems and storage devices are mounted at boot. This guide explains the fstab format, field meanings, mount options, and how to add new entries safely.

IP Command Cheatsheet

Quick reference for using ip command to manage addresses, routes, links, and network diagnostics in Linux

UFW Cheatsheet

Quick reference for managing firewall rules with UFW on Linux

Chmod Cheatsheet

Quick reference for changing file and directory permissions with chmod in Linux

SCP Cheatsheet

Quick reference for secure file transfer with scp over SSH

Wget Cheatsheet

Quick reference for downloading files and mirroring websites with wget

Tar Cheatsheet

Quick reference for creating, listing, extracting, and compressing tar archives in Linux

Screen Cheatsheet

Quick reference for GNU Screen sessions, windows, detach/attach, and common key bindings

How to Parse Command-Line Options in Bash with getopts

This guide explains how to parse command-line options in Bash with getopts, including option strings, OPTARG and OPTIND, error handling, and practical script examples.

Grep Cheatsheet

Quick reference for the grep text search command

SSH Hardening: Best Practices for Securing Your Server

Learn how to harden your SSH server with best practices including key-only authentication, disabling root login, changing the default port, and setting up Fail2Ban.

Bash Positional Parameters

Positional parameters are Bash variables that hold arguments passed to a script or function. Learn how to use $1, $2, $@, $#, and the shift command in Bash.

SSH Cheatsheet

Quick reference for SSH commands and configuration

How to Generate SSH Keys on Linux

Learn how to generate SSH keys on Linux using ssh-keygen, copy them to remote servers, and set up passwordless authentication.

ChatGPT Containers can now run bash, pip/npm install packages, and download files

One of my favourite features of ChatGPT is its ability to write and execute code in a container. This feature launched as ChatGPT Code Interpreter nearly three years ago, was …

Linux Kernel Explorer | reverser.dev

Interactive Linux kernel source code browser with guided learning paths.

Punkbit | Kitty terminal tips and tricks

The Linux Boot Process: From Power Button to Kernel

A detailed walkthrough of the Linux boot process from power button to kernel initialization

Right after reset the CPU jumps to a special address called the reset vector at 0xFFFFFFF0

it finds a disk whose very first 512‑byte sector ends with the marker bytes 0x55 and 0xAA, it treats that device as bootable. BIOS copies that sector to memory at 0x7C00 and jumps there.

How to Fingerprint Websites With WhatWeb - A Practical, Hands-On Guide

Another one of our simple, hands-on pen-testing tutorials. This one teaches you to finger a website for status code, server info, CMS etc.

Imagine you’re curious about what powers a website: the CMS, web server, frameworks, analytics tools, or plugins behind it. WhatWeb can tell you all that right from the Linux command line. It’s like getting a quick peek under the hood of any site.

Modern Linux Tools - Gamedev Guide

Programming notes for Unreal Engine, Houdini, Game Development, Math, & Graphics

Advanced Automation with systemd

Take Your Linux Automation Beyond Cron

Getting Started With Tmux: Absolute Essentials for Beginners

tmux is an excellent productivity tool for pro Linux users who love the terminal. It certainly has a learning curve involved though.

The systemd Playbook: Learn by Doing

Master systemd the practical way—one lab at a time.

Introduction to Flatpak

The universal packaging system from Fedora is popular among developers and desktop Linux users.

Chapter 7: Control Flow With Loops

Let's iterate through the loops.

How to Create a Custom File Type on Linux with a Custom Icon

As a Flutter developer building a Linux desktop app, I recently wanted my app to support a custom file format — let’s call it .maso. My goal was simple: In this post, I’ll walk you through how to set…

Regex Cheatsheet: Essentials You Must Know

Struggling with regex? This simple cheatsheet breaks down common patterns, symbols, and examples you can use right away.

Chapter 1: Introduction to AWK

Learn AWK basics for Linux sysadmins. Master field extraction, built-in variables, and pattern-action syntax with real log analysis examples.

Why Flatpak Apps Use So Much Disk Space On Linux

This tutorial explains why Flatpak apps use so much disk space and are larger in size compared to traditional packages in Linux.

pdfgrep

I Explored the Biggest Man Pages on Linux, Here’s What I Learned

These manuals go large.

10 Tricks You Can Do With FFmpeg on Linux

FFmpeg is way cooler than it sounds.

When you deleted /lib on Linux while still connected via ssh

Let's first not talk about why this can happen, but deleting /lib, /usr/lib, or some other essential runtime files happens quite a lot (as you can see: here, here, here, and here). In this post, I will only discuss what happens when you delete /lib on Linux and how to recover…

Packaging a Python App to Executable .deb Binary

I am sharing how I packaged my python application into an executable .deb package in this tutorial.

10 Essential Bash Shell Commands for Data Science

In this tutorial, we’ll cover 10 essential Bash shell commands every data scientist should know—commands that save time, simplify tasks, and keep you focused on insights rather than busywork.