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CS Foundations

How computers actually work — from transistors and binary through CPU architecture, memory, operating systems, and the internet. The layer below all programming languages.

8 foundational topics Official sources No assumed prior knowledge

Understanding these foundations makes every other programming concept easier. You don't need to know this to write code — but knowing it makes you a significantly better programmer.

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Operating Systems Coming soon

Processes, threads, scheduling, memory management, file systems, and how the OS abstracts hardware for programs.

Networking & the Internet Coming soon

TCP/IP, DNS, HTTP, the OSI model, and how data travels from your browser to a server and back.

Memory & Storage Coming soon

Stack vs heap, RAM vs disk, caching, virtual memory, and why memory layout matters for performance.

Encoding & Compression Coming soon

ASCII, UTF-8, Base64, and how compression algorithms like gzip and zstd make files smaller without losing information.

Security Fundamentals Coming soon

Encryption, hashing, public/private keys, TLS, and why these primitives underpin every secure system.

Performance & Complexity Coming soon

Big-O notation, time vs space trade-offs, cache locality, and how to reason about why code is fast or slow.

Related sections: CS Concepts · Data Structures · Algorithms · How Languages Work