CS Fundamentals

• Computer Science small

  Computer science is the layer underneath your daily tools: how data is arranged in memory, how cost grows with input size, how one machine shares itself…

• Data Structures medium

  A data structure is a way of arranging values in memory so that the operations you need are cheap.

• Computer Networks medium

  A network is a set of machines that agree on how to hand each other small chunks of data.

• Database Internals small

  A database stores data on disk and answers queries about it without losing anything or lying about what it has.

• Concurrency & Async Programming medium

  Concurrency is arranging for a program to make progress on several things at once.

• Regular Expressions (Regex) small

  A regular expression is a small pattern language for describing text.

• Pseudocode small

  Pseudocode is the logic of a program written in plain, structured language instead of a programming language.

• Clean Code medium

  Clean code is code that the next reader can change safely.

• SOLID Principles small

  SOLID is five rules of object design, collected under an acronym by Robert Martin.

• Unit Testing medium

  A unit test exercises one unit — usually a function or a class — in isolation, with every collaborator replaced by a stand-in the test controls.

• Debugging medium

  Debugging is the systematic process of finding why a program does not do what it should.

• Git (Version Control System) medium

  Git is a distributed version control system: every clone holds the full history, and commits form a graph rather than a list.

• Unix Shell medium

  A Unix shell is a program that reads commands, runs them, and connects their input and output.

• Algorithms & Big-O medium

  Big-O is shorthand for how the cost of an algorithm grows as its input grows.

• Operating Systems medium

  An operating system is the layer that shares one machine between many programs.

• Code Reusability small

  Code reusability is the practice of writing a piece of behaviour once and using it in more than one place.

• Code Review medium

  Code review is another person reading a change before it merges, looking for defects the author cannot see.

• Design Patterns medium

  A design pattern is a named solution to a problem that keeps recurring in object-oriented code.

• Refactoring medium

  Refactoring is changing the structure of code without changing what it does.

• Test-Driven Development (TDD) medium

  Test-driven development is the practice of writing a failing test before the code that makes it pass, then improving the code with the test still green.

• Integration Testing medium

  An integration test exercises two or more real components together, across a boundary that a unit test would have replaced — a database, an HTTP endpoint,…

• Git Branching Strategies small

  A branching strategy is a team's shared agreement about what branches mean: how long they live, what may be merged into what, and how a release is cut.

• GitHub small

  GitHub is a hosting service built on top of git, and it adds the parts a repository needs to be a place a team works: remote repositories, pull requests,…

• Command-Line Interface small

  The command-line interface is the habit of reaching for a terminal rather than a graphical tool: typing a command, reading its output, and building the…

• Software Architecture large

  Software architecture is the set of decisions that are expensive to change later: where the boundaries between parts of a system are drawn, who owns which…

• End-to-End Testing medium

  An end-to-end test drives the whole system the way a user does — through the real interface, against real services — and checks that the outcome is right.

• Playwright small

  Playwright is a browser-automation library for writing end-to-end and cross-browser tests.