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121 entries match these filters
- 0455 Which security tool does what? A map for beginners A beginner's map of open source security tool families: vulnerability scanners, secret detection, static analysis, host audits, web application testing, network inventory… Beginner · Explains an idea · Any system Article Security resources & detection · Server hardening 15 Oct 2026
- 0443 Security monitoring explained: IDS, SIEM, EDR and where the logs go A plain language map of the security monitoring tool families, what each one watches, how they feed one another, and where the… Beginner · Explains an idea · Any system Article Detection & threat hunting · Logs 15 Oct 2026
- 0431 What is a detection rule? Sigma explained for beginners A detection rule describes one kind of suspicious activity in logs. Sigma is the shared, tool-independent way to write such rules, so… Beginner · Explains an idea · Any system Article Alerting & dashboards · Security resources & detection 15 Oct 2026
- 0433 What is an awesome list? Awesome lists are hand-curated link collections on GitHub, one per subject, that follow a shared convention. How they work, how to tell… Beginner · Explains an idea · Any system Article Security resources & detection 15 Oct 2026
- 0400 winget: install and update software from the command line winget is the package manager built into Windows. Search for a program, install it by id, update everything with one command and… Beginner · Step by step · Windows Article Installing languages & tools · Windows administration 15 Oct 2026
- 0403 Work across Windows and WSL: files, paths and running tools from both sides WSL is most useful when Windows and Linux cooperate: open Linux folders in Explorer, run Windows programs from bash, convert paths with… Beginner · Step by step · Windows Article Basics · WSL 15 Oct 2026
- 0408 What a reverse proxy is and when you need one A reverse proxy is a server that sits in front of your application, accepts requests from the internet and forwards them to… Beginner · Explains an idea · Any system Article Web servers & reverse proxies 15 Oct 2026
- 0423 Fix: bad interpreter or command not found after a script is copied from Windows (CRLF) A script edited on Windows carries invisible carriage returns, so Linux looks for /bin/bash^M. How to spot CRLF line endings, convert them… Beginner · Fixes an error · Linux, macOS, Windows Article Basics · Shell scripting 15 Oct 2026
- 0397 PowerShell cheat sheet The PowerShell cmdlets and patterns you use every day: files, text, processes, services, filtering, exporting, remoting and the operators that trip up… Beginner · Cheat sheet · Linux, macOS, Windows Article PowerShell 15 Oct 2026
- 0398 Install WSL2 and Ubuntu on Windows One command installs the Windows Subsystem for Linux and Ubuntu. Then learn how to pick a distribution, check which WSL version you… Beginner · Step by step · Windows Article Windows administration · WSL 15 Oct 2026
- 0378 Continuous integration explained What continuous integration means, why small frequent merges plus an automated build on every change prevent integration pain, what a good pipeline… Beginner · Explains an idea · Any system Article Pipelines, runners & hooks 15 Oct 2026
- 0399 Fix: running scripts is disabled on this system (execution policy) PowerShell refuses to run .ps1 files until the execution policy allows it. The usual fix is RemoteSigned for your own user; here… Beginner · Fixes an error · Windows Article PowerShell · Windows administration 15 Oct 2026
- 0379 Your first GitHub Actions workflow: run tests on every push Build a working GitHub Actions pipeline from nothing: a small Python project with a test, a workflow file that runs pytest on… Beginner · Guided project · Any system Article GitHub Actions · Pipelines, runners & hooks 15 Oct 2026
- 0381 pre-commit hooks: catch mistakes before they are committed Install the pre-commit framework, configure hooks for whitespace, YAML and JSON syntax, large files, leaked private keys, Python linting and shellcheck, run… Beginner · Step by step · Linux, macOS, Windows Article Pipelines, runners & hooks · Setup 15 Oct 2026
- 0386 Install Node.js on Linux, macOS and Windows Get Node.js and npm on any desktop OS. Use a version manager (nvm or fnm) when you work on several projects, or… Beginner · Step by step · Linux, macOS, Windows Article Installing languages & tools · Node.js 15 Oct 2026
- 0387 Install Python on Linux, macOS and Windows Install a current Python 3 with pip and venv on each desktop OS, check the version, and avoid the classic traps: python… Beginner · Step by step · Linux, macOS, Windows Article Environments & packages · Installing languages & tools 15 Oct 2026
- 0388 Install Go on Linux, macOS and Windows Install the Go toolchain from the official downloads or a package manager, set PATH so the go command and installed tools are… Beginner · Step by step · Linux, macOS, Windows Article Installing languages & tools 15 Oct 2026
- 0389 Install Java (OpenJDK) on Linux, macOS and Windows Install a current long-term-support OpenJDK with the compiler included, make java and javac available on the command line, and switch between versions… Beginner · Step by step · Linux, macOS, Windows Article Installing languages & tools 15 Oct 2026
- 0390 Install Git on Linux, macOS and Windows Install Git from your package manager, Xcode's command line tools or the Windows installer, confirm the version, and do the one-time configuration… Beginner · Step by step · Linux, macOS, Windows Article Installing languages & tools · Setup 15 Oct 2026
- 0391 Install Docker on Linux, macOS and Windows Docker Desktop or Docker Engine? Pick the right one for your OS, install it, and confirm with docker run hello-world. Covers the… Beginner · Step by step · Linux, macOS, Windows Article Docker basics · Installing languages & tools 15 Oct 2026
- 0392 Install Visual Studio Code on Linux, macOS and Windows Install VS Code from Microsoft's packages, Homebrew or winget, get the code command working in the terminal, and add the extensions you… Beginner · Step by step · Linux, macOS, Windows Article Command-line tools · Installing languages & tools 15 Oct 2026
- 0393 Install PostgreSQL on Linux, macOS and Windows Install the PostgreSQL server and the psql client on each desktop OS, start the service, connect as the postgres superuser and create… Beginner · Step by step · Linux, macOS, Windows Article Install & connect · Installing languages & tools 15 Oct 2026
- 0394 Install kubectl on Linux, macOS and Windows Install the Kubernetes command-line client with curl, a package manager or winget, verify it, and point it at a cluster with a… Beginner · Step by step · Linux, macOS, Windows Article Concepts · Installing languages & tools 15 Oct 2026
- 0395 Install Rust on Linux, macOS and Windows Install Rust the official way with rustup, which brings rustc, cargo and future updates, make sure a C linker is present, and… Beginner · Step by step · Linux, macOS, Windows Article Installing languages & tools 15 Oct 2026
- 0396 PowerShell basics: cmdlets, objects and the pipeline PowerShell commands are called cmdlets, they return objects instead of text, and the pipeline passes those objects between them. Once that clicks,… Beginner · Explains an idea · Linux, macOS, Windows Article PowerShell 15 Oct 2026
- 0357 Keep secrets out of git: .env files, gitignore and what to do after a leak Load passwords and API keys from an untracked .env file, commit a safe .env.example instead, catch mistakes before they are pushed, and… Beginner · Step by step · Any system Article Housekeeping · Secrets & access 15 Oct 2026
- 0362 The 3-2-1 backup rule, and why a backup you never restored is not a backup Three copies, two kinds of media, one off-site: what the rule really protects against, how it maps to real tools, and why… Beginner · Explains an idea · Any system Article Strategy & restore drills 15 Oct 2026
- 0345 SSH keys: create, copy and use them Generate an ed25519 key pair, install the public key on a server with ssh-copy-id, keep the private key protected with a passphrase… Beginner · Step by step · Linux, macOS, Windows Article Keys & config · SSH 15 Oct 2026
- 0355 TLS certificates explained What a certificate proves, who signs it, what the chain and expiry mean, and how to read any site's certificate from the… Beginner · Explains an idea · Any system Article TLS & certificates 15 Oct 2026
- 0327 Docker images, containers and volumes explained An image is a read-only template, a container is a running copy of it with a thin writable layer, and a volume… Beginner · Explains an idea · Linux, macOS, Windows Article Docker basics 15 Oct 2026
- 0329 Docker CLI cheat sheet The Docker commands you reach for every day, grouped by what they act on: containers, images, volumes, networks, logs and cleanup, with… Beginner · Cheat sheet · Linux, macOS, Windows Article Docker basics 15 Oct 2026
- 0334 Fix: port is already allocated docker run or docker compose up fails with Bind for 0.0.0.0:8080 failed: port is already allocated. Find what holds the port, another… Beginner · Fixes an error · Linux, macOS, Windows Article Docker fixes · Processes & ports 15 Oct 2026
- 0340 Build and run a small Python web app in a container Write a tiny Flask app, give it a Dockerfile, build the image, run it with a published port, make a change and… Beginner · Guided project · Linux, macOS, Windows Article Basics · Docker basics · Images & registries 15 Oct 2026
- 0291 What is a log? A log is a running record of what a program did and when, written to a file so you can look back… Beginner · Explains an idea · Any system Article Logs 15 Oct 2026
- 0307 What is encryption? Encryption scrambles data with a key so only someone with the right key can read it again. Beginner · Explains an idea · Any system Article TLS & certificates 15 Oct 2026
- 0292 What is a database? A database is an organised store of data that programs can search, update and share safely, even with many users at once. Beginner · Explains an idea · Any system Article Choosing a database 15 Oct 2026
- 0308 What is a backup snapshot? A snapshot is a frozen picture of a disk or system at one moment that you can roll back to if something… Beginner · Explains an idea · Any system Article Strategy & restore drills 15 Oct 2026
- 0293 What is SQL? SQL is the language you use to ask a relational database questions and to add, change or delete its data. Beginner · Explains an idea · Any system Article Queries 15 Oct 2026
- 0309 What is RAID? RAID combines several disks into one so data survives a disk failure or is read and written faster. Beginner · Explains an idea · Any system Article Disks, LVM & filesystems 15 Oct 2026
- 0294 What is an index (database)? A database index is a lookup structure that lets the database find rows fast instead of reading the whole table. Beginner · Explains an idea · Any system Article Indexes & performance 15 Oct 2026