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86 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
- 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
- 0418 Bash scripting fundamentals: variables, conditions, loops, functions The core building blocks of a bash script: variables and quoting, if and test, for and while loops, functions, exit codes and… Beginner · Explains an idea · Linux, macOS Article Basics · Shell scripting 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
- 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
- 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
- 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
- 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
- 0341 DNS, IP addresses and ports explained for beginners An IP address says which machine, a port says which program on it, and DNS turns names into addresses. The three ideas… Beginner · Explains an idea · Linux, macOS Article DNS, IP addresses & ports 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
- 0310 What is a cluster? A cluster is a group of computers working together as one system so that if one fails the others keep the service… Beginner · Explains an idea · Any system Article Clusters & high availability 15 Oct 2026
- 0295 What is a transaction? A transaction groups several database changes so they all happen together or not at all, keeping the data consistent. Beginner · Explains an idea · Any system Article Queries 15 Oct 2026
- 0311 What is Kubernetes? Kubernetes is a system that runs containers across many servers, restarting, scaling and connecting them automatically. Beginner · Explains an idea · Any system Article Concepts 15 Oct 2026
- 0296 What is a primary key? A primary key is the column that uniquely identifies each row in a table, like an ID number nobody else can have. Beginner · Explains an idea · Any system Article Queries 15 Oct 2026
- 0312 What is a pod? A pod is the smallest unit Kubernetes runs: one or more containers that share a network address and storage. Beginner · Explains an idea · Any system Article Workloads & services 15 Oct 2026
- 0297 What is a foreign key? A foreign key is a column that points to the primary key of another table, linking related rows together. Beginner · Explains an idea · Any system Article Joins 15 Oct 2026
- 0313 What is CI/CD? CI/CD is the habit of automatically testing every code change and, once it passes, deploying it without manual steps. Beginner · Explains an idea · Any system Article Pipelines, runners & hooks 15 Oct 2026
- 0298 What is JSON? JSON is a simple text format for structured data, made of names, values, lists and nested objects, used everywhere on the web. Beginner · Explains an idea · Any system Article CSV & JSON 15 Oct 2026
- 0314 What is a pull request? A pull request asks teammates to review and merge the changes on your branch into the main branch. Beginner · Explains an idea · Any system Article Pull requests 15 Oct 2026
- 0299 What is YAML? YAML is a human friendly text format for configuration files where indentation shows structure instead of brackets. Beginner · Explains an idea · Any system Article CSV & JSON 15 Oct 2026
- 0315 What is open source? Open source software is software whose code anyone can read, change and share under a licence that allows it. Beginner · Explains an idea · Any system Article Pull requests 15 Oct 2026
- 0300 What is a REST API? A REST API is a web API where you use normal HTTP requests on URLs to read, create, update and delete things. Beginner · Explains an idea · Any system Article Making requests 15 Oct 2026
- 0301 What is HTTP? HTTP is the request and response language that browsers, apps and servers use to exchange web pages and data. Beginner · Explains an idea · Any system Article Making requests 15 Oct 2026
- 0302 What is a status code? A status code is the three digit number a web server returns to say whether a request worked, like 200 OK or… Beginner · Explains an idea · Any system Article Status codes 15 Oct 2026
- 0303 What is CORS? CORS is a browser rule that decides whether a web page from one site is allowed to call an API on another… Beginner · Explains an idea · Any system Article Making requests 15 Oct 2026
- 0304 What is a cookie? A cookie is a small piece of text a website stores in your browser so it can recognise you on the next… Beginner · Explains an idea · Any system Article Authentication 15 Oct 2026
- 0289 What is a process? A process is a running program; the operating system gives each one its own memory and an ID number. Beginner · Explains an idea · Any system Article Processes & ports 15 Oct 2026
- 0305 What is a token? A token is a string that proves who you are or what you may do, sent with requests instead of a password. Beginner · Explains an idea · Any system Article Authentication 15 Oct 2026
- 0290 What is a cron job? A cron job is a command scheduled to run automatically at set times, such as every night at two o'clock. Beginner · Explains an idea · Any system Article cron & timers 15 Oct 2026
- 0306 What is hashing? Hashing turns any data into a fixed length fingerprint that cannot be reversed, used to check files and store passwords. Beginner · Explains an idea · Any system Article Secrets & access 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
- 0276 What is SSH? SSH is a secure way to open a command line on another computer over the network, with everything encrypted. Beginner · Explains an idea · Any system Article SSH 15 Oct 2026