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Step-by-step guides on Linux, networking, operating systems, audit and security, written from real configurations and lab notes.
● 153 free guidesLinux30 guides
View all 30 →What Is Linux? History, Distributions and File System
What is the Linux operating system? Its history from Unix and GNU, how the kernel and distributions work,…
3 min read 0210 Reasons to Use Linux in 2026
Ten practical reasons to use Linux in 2026: cost, security, stability, control, cloud, developer tools, older hardware and…
3 min read 035 Linux Predictions for 2022: What Actually Happened
We look back at five popular Linux predictions for 2022, from Linux gaming to Wayland and Flatpak, and…
3 min read 04Difference Between Linux and Unix: History, Licensing and Use Today
The difference between Linux and Unix: history, licensing, kernels, POSIX and certification, examples like AIX and macOS, and…
3 min read 05Difference Between Linux and Windows: A Practical Comparison
The difference between Linux and Windows explained: licensing, kernel, file system, users and permissions, software, security, servers and…
4 min read 06Linux Fundamentals and Basic Commands for Beginners
Linux fundamentals and basic commands for beginners: the shell, paths, files and directories, searching text, permissions, processes and…
3 min readNetworking36 guides
View all 36 →What Are the Internet and Networking? A Beginner’s Guide
Internet and networking basics for beginners: what a network is, LAN, MAN and WAN, how the internet began,…
3 min read 02Network Devices and Network Topologies Explained
Network devices and topologies explained: modems, NICs, hubs, switches, routers, gateways and firewalls, plus bus, star, ring, mesh…
3 min read 03What Is a MAC Address? Format, Types and Why We Need It
What a MAC address is, its format and OUI, MAC address types (unicast, multicast, broadcast), MAC vs IP,…
3 min read 04What Is an IP Address? IPv4 and IPv6 Explained
What an IP address is, how IPv4 and IPv6 work, binary conversion, address classes and CIDR, private ranges,…
3 min read 05Internet and Web Technology Basics: Internet vs Web, URLs and DNS
Internet and web technology basics: the internet vs the web, URI vs URL, how DNS works, who governs…
4 min read 06Top Networking Certifications in 2026: Which One Should You Get?
A guide to the top networking certifications: CompTIA Network+, Cisco CCNA, CCNP and CCIE, Juniper and cloud networking,…
3 min readOperating systems15 guides
View all 15 →What Is an Operating System? Definition, Examples and How It Works
What is an operating system? A clear definition, what an OS does, how it boots, its main parts,…
3 min read 02Types of Operating Systems (OS) Explained with Examples
The main types of operating systems explained: batch, time-sharing, distributed, network, real-time, mobile, embedded and desktop, with examples.
4 min read 03Functions of Operating System: 10 Core Jobs Explained with Examples
The main functions of operating system software explained: process, memory, file, device and storage management, security, networking and…
4 min read 04Process Management in Operating System: States, PCB, Scheduling and fork()
Process management in operating system explained: process vs program, process states, the PCB, context switching, and process creation…
4 min read 05Threads in Operating System: Processes vs Threads, Models and Examples
Threads in operating system explained: what a thread is, threads vs processes, user and kernel threads, threading models,…
3 min read 06CPU Scheduling Algorithms Explained with Examples
CPU scheduling algorithms explained: FCFS, SJF, SRTF, priority, round robin and multilevel queues, with a worked example and…
4 min readAudit & compliance46 guides
View all 46 →Audit, Compliance and Governance: How GRC Fits Together
Audit, compliance and governance explained: what each means, how they differ, how they work together with risk management…
3 min read 02What Is an Assessment? Types and Methods of Security Assessment
The main types and methods of assessment in cybersecurity and compliance: gap, risk, vulnerability, penetration, maturity and vendor…
3 min read 03Audit vs Assessment: What Is the Difference?
Audit vs assessment in cybersecurity and compliance: purpose, independence, criteria, evidence and outcome compared, with examples and when…
4 min read 04Why Audits Matter: The Importance and Requirements of an Audit
The importance of an audit for businesses: trust, compliance, risk reduction and better decisions, when audits are legally…
3 min read 05What Does an Organization Need to Do to Be Compliant? 10 Practical Steps
How to achieve regulatory compliance in 10 steps: map your obligations, assess gaps, set policies and controls, train…
5 min read 06What Happens If an Organization Does Not Comply with Compliance Laws?
The consequences of non-compliance with laws like the DPDP Act, GDPR and PCI DSS: fines, lawsuits, lost licences,…
5 min readCyber warfare16 guides
View all 16 →What Is Cyber Warfare? Definition, Key Terms and History
What is cyber warfare? A clear definition, the key terms (cyberspace, information warfare, C2), how it differs from…
3 min read 02Reasons for Cyber War and Warfare
What drives cyber warfare? The main reasons states and groups wage cyber war: espionage, sabotage, political pressure, economic…
4 min read 03Advantages and Disadvantages of Cyber Warfare
The advantages of cyber warfare (low cost, deniability, reach) and its disadvantages (escalation, collateral damage, weak rules), with…
5 min read 047 Types of Cyber Warfare Attacks, with Real Examples
The main types of cyber warfare: espionage, sabotage, DDoS, attacks on power grids, propaganda, economic disruption and surprise…
3 min read 05Cyber Warfare Case Study: The SolarWinds Supply Chain Attack (2020)
A cyber warfare case study of the 2020 SolarWinds attack: how the SUNBURST supply chain compromise worked, who…
3 min read 06Levels of Cyber Warfare: Strategic, Operational and Tactical
The three levels of cyber warfare explained: strategic, operational and tactical, who works at each level, the skills…
3 min readDevOps & Kali Linux10 guides
What Is DevOps? Principles, Lifecycle, Tools and Careers
What is DevOps? The culture and principles behind it, the DevOps lifecycle, CI/CD, key tools by stage, how…
3 min read 02Introduction to Kali Linux: A Guide for Beginners
Kali Linux for beginners: what Kali is, who uses it, its history, key features and tools, system requirements,…
3 min read 03Kali Linux vs Parrot OS (2026): Which Should You Use?
Kali Linux 2026.2 vs Parrot OS 7.4 compared: base, release model, tools, desktop, privacy, editions and a clear…
9 min read 04How to Self-Host n8n on Linux with Docker Compose, PostgreSQL and HTTPS (2026)
Set up a production-ready self-hosted n8n on Linux: Docker Compose, PostgreSQL 18, automatic HTTPS with Caddy, a first…
8 min read 05HTTP2Shell (CVE-2026-111497): Patch Brotli Beyond Node.js
HTTP2Shell (CVE-2026-111497) hits Brotli in Bun, Python, Envoy, Istio and Linux distros. Fixed versions, tested checks and proxy…
10 min read 06Pillow Vulnerability CVE-2026-112900: EPS Flaw, Fix and Checks
Pillow vulnerability CVE-2026-112900 lets crafted EPS filenames inject Ghostscript options. Check your version, upgrade to 13.0.0 and lock…
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