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67 entries match these filters
- 0284 What is a shell? A shell is the program that reads the commands you type and tells the operating system to run them. Beginner · Explains an idea · Any system Article Basics 15 Oct 2026
- 0269 What is a commit? A commit is a saved snapshot of your project in Git, with a message explaining what changed and why. Beginner · Explains an idea · Any system Article Branching & rebasing 15 Oct 2026
- 0285 What is a terminal? A terminal is the window where you type commands; the shell inside it does the actual work. Beginner · Explains an idea · Any system Article Basics 15 Oct 2026
- 0270 What is a branch? A branch is a separate line of work in Git, so you can try changes without touching the main version of the… Beginner · Explains an idea · Any system Article Branching & rebasing 15 Oct 2026
- 0286 What is PATH? PATH is the list of folders your shell searches to find a program when you type its name. Beginner · Explains an idea · Any system Article Basics 15 Oct 2026
- 0271 What is a merge conflict? A merge conflict happens when two branches changed the same lines and Git needs a human to decide which version wins. Beginner · Explains an idea · Any system Article Branching & rebasing 15 Oct 2026
- 0287 What is an environment variable? An environment variable is a named value the operating system passes to programs, such as settings or secrets. Beginner · Explains an idea · Any system Article Basics 15 Oct 2026
- 0272 What is a virtual machine? A virtual machine is a complete computer made of software, running inside another computer with its own operating system. Beginner · Explains an idea · Any system Article Basics 15 Oct 2026
- 0288 What is a daemon or service? A daemon or service is a program that runs in the background all the time, waiting to do its job without a… Beginner · Explains an idea · Any system Article Services & systemd 15 Oct 2026
- 0273 What is a hypervisor? A hypervisor is the software layer that creates and runs virtual machines and shares the real hardware between them. Beginner · Explains an idea · Any system Article Basics 15 Oct 2026
- 0274 What is DNS? DNS is the internet's phone book: it turns names like example.com into the IP addresses computers actually use. Beginner · Explains an idea · Any system Article DNS, IP addresses & ports 15 Oct 2026
- 0275 What is an IP address? An IP address is the unique number that identifies a device on a network so data knows where to go. Beginner · Explains an idea · Any system Article DNS, IP addresses & ports 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
- 0277 What is TLS? TLS is the encryption layer that puts the S in HTTPS, protecting data between your browser and a server. Beginner · Explains an idea · Any system Article TLS & certificates 15 Oct 2026
- 0278 What is a certificate? A certificate is a digital ID card that proves a website or server is genuine, issued by a trusted authority. Beginner · Explains an idea · Any system Article TLS & certificates 15 Oct 2026
- 0279 What is a reverse proxy? A reverse proxy is a server that sits in front of your apps, receives all requests and forwards them to the right… Beginner · Explains an idea · Any system Article Web servers & reverse proxies 15 Oct 2026
- 0280 What is a firewall? A firewall is a filter that decides which network connections are allowed in or out of a computer or network. Beginner · Explains an idea · Any system Article Firewalls 15 Oct 2026
- 0281 What is a package manager? A package manager is a tool that installs, updates and removes software for you and keeps track of what depends on what. Beginner · Explains an idea · Any system Article Packages & updates 15 Oct 2026
- 0241 Choosing a database: relational, document or key-value Relational databases, document stores like MongoDB and key-value stores like Redis each fit different jobs. An honest look at what each does… Beginner · Explains an idea · Any system Article Choosing a database · Database operations 15 Oct 2026
- 0231 MongoDB documents and collections compared with SQL tables MongoDB stores data as JSON-like documents grouped in collections instead of rows in tables. This explains the model, the _id field, embedding… Beginner · Explains an idea · Any system Article Basics · Choosing a database 15 Oct 2026
- 0187 Terraform concepts: providers, state, plan and apply, modules, and OpenTofu Terraform describes infrastructure in code, compares it with what exists, and changes only the difference. Learn providers, resources, state, the plan/apply loop,… Beginner · Explains an idea · Any system Article Terraform 15 Oct 2026
- 0072 CSV vs JSON: choosing a format and avoiding the classic pitfalls CSV is a simple table of text; JSON holds nested, typed data. Both break in predictable ways: quoting, delimiters, encodings, numbers and… Beginner · Explains an idea · Any system Article CSV & JSON 15 Oct 2026
- 0081 How an HTTP request works: methods, headers, and body An HTTP request is a short text message a client sends to a server: a method and path, some headers, and sometimes… Beginner · Explains an idea · Any system Article Making requests 15 Oct 2026
- 0016 let, const and var: variables and scope in JavaScript Use const by default, let when a value must change, and avoid var. The difference is about scope: where a variable is… Beginner · Explains an idea · Any system Article Basics 15 Oct 2026
- 0024 TypeScript basics: types, interfaces, unions and narrowing TypeScript adds type annotations to JavaScript and checks them before your code runs. These are the core ideas you need to read… Beginner · Explains an idea · Any system Article Basics 15 Oct 2026
- 0033 The everyday Git workflow: status, add, commit, push, pull Git moves your changes through three places: the working folder, the staging area, and the commit history. These five commands, plus .gitignore… Beginner · Explains an idea · Any system Article Housekeeping · Setup 15 Oct 2026
- 0001 Virtual environments with venv A virtual environment is a private folder of Python packages for one project, so projects never fight over versions. Create one with… Beginner · Explains an idea · Any system Article Environments & packages 15 Oct 2026