Mathematics & Theoretical CS: what Hacker News watches
9 topics, 358 videos. Pick a topic for a focused list, or scan the 100 best-scored across the whole area below.
- HN repeatedly cites it as the definitive explanation of SwissTable, the design behind Abseil, Rust's hash map and Go's maps.
- Reducible explainer recommended in 8 different months by 7 HN users, 2021–2026HN repeatedly calls it a fantastic explanation that made FFT click, with some rewatching it periodically.
- HN treats it as the definitive, engaging talk on hash table internals and Python dict ordering, and recommends it in tech-talk lists.
- A perennial recommendation for anyone learning performance optimization, cited whenever hash tables, cache behavior or STL containers come up.
- HN people point to it for rrb-trees, text editor data structures and bringing Clojure-style persistent structures to C++.
- HN recommends it as an entertaining talk that starts simple and goes deep on practical performance optimization.
- It is the default link in any thread about boarding or deplaning order, praised as an excellent, clear treatment.
- HN commenters call it a must-watch for its deadpan, absurdly elaborate engineering and cite it for ideas like diluting strong engines with random moves.
- HN readers recommend it as the best introduction to robust-first computing, where randomness and fault tolerance are built into the architecture.
- HN fans love it for Knuth's humor and for how he makes open math problems feel approachable, and it is often cited for details like dancing links and counting rectangle subdivisions.
- Strongly recommended as a beautiful demonstration that APL can be read and reasoned about step by step.
- HN regards it as one of the best technical talks, a deep and clear walkthrough of scalable lock-free hash tables built on compare-and-swap.
- Defunctland documentary recommended in 4 different months by 7 HN users, 2021–2024HN recommends it as an accessible, engrossing lesson in queueing theory and systems design, even for people with no interest in Disney.
- HN points to it as a clear explanation of immutable data structures such as tries, and of the case for immutability with React and Flux.
- Strongly recommended as a clear, accessible survey of the CRDT landscape.
- Recommended as an approachable introduction to CRDTs and the local-first idea behind apps like Actual.
- HN commenters call it a beautiful, brilliant demonstration of APL's expressiveness and a model of clear narration.
- HN points to it as a clear lesson that algebraic properties like associativity unlock parallelism, applicable in any language.
- HN links it whenever menu hover problems or nearest-to-pointer selection come up, and as proof algorithms matter in front-end work.
- Recommended as a clear introduction to dynamic programming from a well-regarded instructor.
- Life at Google demo recommended in 3 different months by 2 HN users, 2017–2020Cited as a realistic, well-run example of a technical interview, both for candidates preparing and interviewers calibrating.
- Anders Brownworth tutorial recommended in 3 different months by 3 HN users, 2017–2025HN repeatedly recommends it as the best ground-up, non-hype introduction for people who want to understand what a blockchain actually is.
- Timo Bingmann demo recommended in 4 different months by 4 HN users, 2014–2023A classic that HN points to for seeing how sorting algorithms behave, valued for how satisfying it is to watch and hear.
- HN points people to it as the explanation that finally made Fourier transforms and the FFT click, with a good historical story.
- Commenters say it changes how you think about types and the STL, and makes a case for simple modern C++.
- Redis talk recommended in 3 different months by 3 HN users, 2018–2023Recommended in graph database threads as a mind-blowing case for expressing graph analysis as linear algebra.
- Martin Donald explainer recommended in 3 different months by 3 HN users, 2021–2022Commenters recommend it as the clearest way to understand WFC, especially in threads about Townscaper and tiled content generation.
- HN calls it a surprisingly fun, approachable talk on a hard problem and cites it in floating-point threads.
- Polylog explainer recommended in 3 different months by 4 HN users, 2024–2026Recommended as an intuitive, animated explanation of P vs NP framed around reversing computation.
- LuceneSolrRevolution talk recommended in 3 different months by 3 HN users, 2019–2020HN recommends it as an instructive, easy-to-follow look at Lucene internals from a core committer.
- Nemean explainer recommended in 3 different months by 3 HN users, 2021–2022HN recommends it as an approachable explanation that makes the famous algorithm finally make sense.
- Martin Kleppmann talk recommended in 3 different months by 3 HN users, 2020–2024Recommended as an excellent first education on CRDTs and their limits.
- HN recommends it as a clear, high-quality introduction to succinct data structures from a leading authority.
- Robin Baumgarten demo recommended in 3 different months by 3 HN users, 2009–2012HN points to it as a vivid demo that plain A* search can beat fancier machine-learning approaches in game AI.
- Recommended in cache-algorithm threads as a fun, informative walk through caching strategies and ARC.
- HN recommends it as an entertaining demonstration of how powerful algorithmic gerrymandering can be.
- HN points to it as a simple diff-and-patch alternative to operational transforms and CRDTs for collaborative editing.
- HN people point to it for intuition about why some games are hard to navigate and for its Rush Hour and graph visualizations.
- Dyalog User Meetings talk recommended in 3 different months by 3 HN users, 2019–2021HN recommends it as a striking example of high-performance tree handling with array programming.
- HN points to it as the best explanation of simdjson internals and of why fast parsing is rarely disk-bound.
- AlgoRythmics demo recommended in 2 different months by 2 HN users, 2013–2021HN recommends it as a memorable and fun way to visualize how sorting algorithms work.
- Cited as an excellent look at Knuth's thinking and working style, and as a likely source for quotes about his habits.
- HN points to it as the authoritative talk on Swiss tables, their design rationale, and real-world effects like Hyrum's law.
- Recommended as a thorough, well-regarded explanation of hash table design tradeoffs and why the standard container is a poor choice.
- Tom Scott plus demo recommended in 2 different months by 2 HN users, 2022–2026HN people link it in discussions of taxi drivers' spatial memory and how cabbies handle roadworks and traffic.
- HN commenters point to it as programming inspiration and as a source of Bentley's anecdotes about adding function by deleting code.
- HN points to it as a solid, if long, introduction to B-epsilon trees and why BetrFS is built the way it is.
- HN cites it as an excellent example of solving small cases to find a pattern, and as a favorite puzzle with an elegant binary solution.
- HN recommends it as the go-to explanation of optimal Wordle openers like CRANE and a friendly introduction to information theory, also relevant to Mastermind.
- ACCU Conference talk recommended in 1 different month by 1 HN user, 2016–2021HN recommends it as a careful, entertaining talk on low-level optimization that shows how textbook algorithms can be sped up.
- Edward Kmett talk recommended in 1 different month by 1 HN user, 2017–2025Commenters credit it as the place they first learned about succinct data structures, and found it left a lasting impression.
- switchbg music video recommended in 1 different month by 1 HN user, 2021–2026HN shares it as a fun, memorable way to explain the longest path problem and as an entry in lists of programming and math songs.
- Uber Engineering talk recommended in 1 different month by 1 HN user, 2018–2025HN points to it as the detailed explanation of why hexagons suit map grids, in threads about H3.
- Cited as a fun example of how algorithmic changes can yield enormous performance gains.
- fragglet demo recommended in 1 different month by 1 HN user, 2019–2023HN fondly recalls it as the ideal visual demonstration of sorting algorithms and as the thing that got some people into programming.
- Cited as the source for criticism of std::deque and move-constructor pitfalls, and as motivation to write custom data structures.
- pkrumins talk cited on HN 6 times, 2017–2023Used as the go-to citation in LeetCode and hiring debates that competitive programming skill is not a good signal for hiring.
- Zelexi demo cited on HN 4 times, 2010–2011Cited in discussions of voxel rendering, id Software's research and Euclideon-style claims as an early demonstration of the technique.
- weedipikia comedy video cited on HN 3 times, 2013–2019Used as a joke or aside about bubble sort and as evidence that Obama was tech savvy, not as something recommended for its content.
- Cited as the standard example of algorithmic redistricting when gerrymandering and electoral reform come up.
- HN recommends it repeatedly as one of the best and most entertaining programming talks, and as the talk that makes the Y combinator click, even for people who do not use Ruby.
- HN commenters call it one of the best security talks and the standard introduction to LANGSEC, which they use to argue for simpler, well-specified input formats.
- HN regards it as an entertaining and eye-opening introduction to why logic and functional programming are connected, and it is a frequent pick in favorite-tech-talk threads.
- HN calls it a legendary, clearly explained hacker talk whenever mov-only computing or anti-decompilation comes up.
- HN commenters recommend it as a clear, accessible introduction to incompleteness and the self-referential proof idea.
- HN repeatedly names it as one of the funniest and best talks, a favorite example of absurd computation.
- Phillip Bradbury demo recommended in 6 different months by 6 HN users, 2013–2025The canonical visual for nested simulation, Turing completeness and self-reference; HN readers call it mind-blowing and reach for it constantly.
- Fullstack Academy lecture recommended in 5 different months by 5 HN users, 2019–2024Repeatedly recommended as one of the most approachable introductions to lambda calculus and combinators.
- HN recommends it as an accessible explanation of number categories and why almost all numbers are unknowable.
- hackerdashery explainer recommended in 5 different months by 4 HN users, 2015–2026HN repeatedly recommends it as the best short, funny introduction to P vs. NP and complexity classes for people with no background.
- Strongly recommended in lambda calculus and Y-combinator threads as a mind-expanding half hour that clarifies the ideas.
- PyCon 2019 tutorial recommended in 4 different months by 4 HN users, 2019–2021HN calls it a brilliant, mind-bending introduction to lambda calculus for programmers.
- Repeatedly recommended in best-talks threads as a fun, mind-blowing demonstration of unexpected computation.
- Recommended as a jaw-dropping, must-see talk that gives an amazing intro to static analysis alongside Might's personal story.
- HN points to it as an accessible long-form introduction to Wolfram's ideas and a window into his passion, though some are critical of his claims.
- HN recommends it for getting the inventors of major concurrency models together, disagreements included.
- HN recommends it as an accessible way into Wolfram's physics ideas and his personality.
- HN likes it as a funny, entertaining presentation, frequently linked in threads on NP-hardness of games and NES automation.
- HN recommends Sipser's free lectures as the companion to the standard theory of computation textbook and a path to understanding how computers fundamentally work.
- Recommended as a companion to reading the dense book.
- Because Science demo recommended in 3 different months by 3 HN users, 2019–2026HN links it as the accessible, hands-on demo behind the claim that Magic is Turing complete.
- Giroux Studios explainer recommended in 2 different months by 2 HN users, 2016–2022Recommended in large-number threads as going further than other popular videos on Graham's number and ordinals.
- HN points to it as a detailed explanation of Wolfram's physics hypothesis, and for Wolfram's evident passion, though some find it long.
- Offered as a short, clear explanation of the halting problem and its link to decidability.
- Cited whenever commenters want to note that Conway did not enjoy being known mainly for the Game of Life.
- Mentioned in lambda calculus and combinator threads as a visual entry point to the topic.
- Harvard CMSA lecture recommended in 1 different month by 1 HN user, 2025Pointed to in Busy Beaver threads as an accessible expert talk on the topic.
- BaronWable demo recommended in 1 different month by 1 HN user, 2016–2025HN cites it as an impressive example of building computation inside Dwarf Fortress.
- LarryNorman lecture recommended in 1 different month by 1 HN user, 2008–2014Cited in debates over whether computer science is a science, and for Abelson's line that it is neither a science nor about computers.
- TCGplayer demo cited on HN 4 times, 2017–2023Cited as the real-world example of an inescapable loop in Magic: The Gathering, in discussions of its Turing completeness.
- Rational Animations demo cited on HN 4 times, 2016–2024HN commenters use it as an illustration of how simple rules can produce surprisingly complex behavior.
- MatthiasWandel demo cited on HN 8 times, 2013–2021HN cites it as the classic example of a mechanical binary adder and a source of inspiration for marble-based computers.
- It is HN's most frequently recommended starting point for quantum computing because it avoids pop-science hand-waving and needs only basic linear algebra.
- PBS Infinite Series explainer recommended in 4 different months by 4 HN users, 2017–2023HN recommends it as one of the most accessible yet accurate introductions to quantum computing, and part of a wider series that covers Shor's algorithm.
- HN recommends it as a good overview of the NIST candidates and the state of post-quantum crypto.
- HN commenters point to it as a clear, approachable explanation of Shor's algorithm and what quantum computers actually do.
- PBS Infinite Series explainer recommended in 3 different months by 3 HN users, 2018–2019HN recommends it as a clear, worked explanation of Shor's algorithm for building intuition.
- Qiskit talk recommended in 2 different months by 2 HN users, 2021–2024HN recommends it as an oral history of the algorithm straight from its inventor.
- HN points to it both as an approachable quantum computing intro and as an example of explaining one concept at multiple levels.
- Arthur Gleckler talk recommended in 2 different months by 3 HN users, 2017–2019Recommended as a real-world case of Lisp in a cutting-edge industry, applied to quantum hardware.
Showing the 100 best-scored of 358. Use search to find the rest.