youtube algorithm

A JSConf 2014 talk visually breaking down algorithms behind everyday UI patterns, such as dropdown menus that vanish when the mouse drifts and picking the nearest target to the cursor. It shows how these are implemented in JavaScript.

A PyCon 2012 talk by early YouTube engineer Mike Solomon on how YouTube scaled its architecture, which is mostly Python.

Numberphile visits YouTube to learn why view counts on new videos used to freeze at 301. It explains that YouTube holds counts while it verifies views aren't from bots or fakes.

Cuong Do of YouTube describes how a handful of engineers scaled the site, covering hardware, software and database scalability challenges during its rapid growth. The talk was given at the 2007 Seattle Conference on Scalability.

Glenn Vanderburg presents Cló, a Clojure library that reimplements TeX's core typesetting algorithms as composable functions. He shows what translating procedural, literate-programming code into functional form teaches.

Psychologist Robert Epstein presents a Stanford EE380 colloquium on how internet algorithms such as search rankings can manipulate opinions, purchases and votes at massive scale. He also describes a new monitoring system for tracking such influence.

A three-minute capture of SORTDEMO.BAS, the sorting visualization that shipped with QBasic. It animates insertion, bubble, heap, exchange, shell and quick sort with chiptune-like sound.

Guy Steele presents a small geometric problem and compares four computational approaches: a classic sequential solution and three parallel-friendly ones. Each is illustrated pictorially and with working code, weighing total work against time to solution.

Sean Parent's GoingNative 2013 talk surveys new and overlooked C++ features and shows how to use them for simple, correct, clear code. It stresses using standard algorithms rather than raw loops.

Chris Stucchio presents the ethical principles behind algorithmic decision making and shows with examples from lending, criminology and education that they cannot all be satisfied at once. The talk frames AI fairness as a set of quantitative tradeoffs.

A restored 1994 video of Karl Sims' research on evolved virtual creatures, where simulated block creatures are bred through artificial evolution to swim, walk, follow and compete. It is a landmark demonstration of genetic algorithms in physics simulation.

Bryan Cantrill presents the ARC (Adaptive Replacement Cache) paper by Megiddo and Modha at Papers We Love. He opens with a survey of caching strategies before digging into the self-tuning LRU/MFU design.

Lukas Eder's Devoxx talk on how modern cost-based SQL optimizers rewrite and plan queries in ways developers would not expect. It argues that declarative SQL, used well, can run complex queries very fast.

Jon Bentley walks through three implementations of Hoare's Quicksort, from a dozen-line C function to a series of systematic code transformations that make the program ever simpler and more powerful. It is a Google Tech Talk on code elegance and program derivation.

Edward Kmett's 2013 talk at Prezi in Budapest on succinct data structures, which store data in close to the information-theoretic minimum space while supporting fast queries. It ties together the research and walks through his Haskell succinct library.

Donald Knuth explains at Stanford's CCRMA the constraint-based methods he is using to compose a major work for pipe organ.

ETH Zurich researchers demonstrate a quadrocopter that keeps flying stably after losing a motor and propeller entirely, with the algorithm running onboard while a pilot flies it.

The question-and-answer session that followed Jonathan Blow's talk on dealing with lack of motivation, malaise and depression. It is hosted on YouTube as a mirror of a Twitch recording.

Eben Moglen's 2011 Personal Democracy Forum talk on the loss of anonymity and privacy on the internet. He proposes building an alternative net of personal servers, the idea behind FreedomBox.

Julia co-creator Stefan Karpinski explains why multiple dispatch makes Julia code and types reusable across packages with so little friction. He covers sharing basic types and sharing generic algorithms.

Damian Conway's hour-long keynote at the Perl conference, On the Shoulders of Giants, showing off Perl 6 (Raku) features with history, algorithms and a quantum math operator built with grammars. It is delivered with comic flair.

A Dyalog demonstration of developing a Sudoku solver in APL, using an algorithm by Arthur Whitney with performance work by John Scholes. The narration steps through the array-oriented solution.

John Ousterhout lectures on the Raft consensus algorithm, made for the Raft user study comparing how students learn Raft and Paxos. It covers leader election and log repair.

Conal Elliott presents his paper on automatic differentiation, deriving a simple, generalized AD algorithm from a natural specification. Varying the representation of derivatives yields forward and reverse mode algorithms that avoid the complexity and statefulness of backpropagation.

Martin Kleppmann's QCon London 2018 talk on keeping data consistent in distributed systems without a central leader. It surveys CRDT algorithms for syncing devices and collaborative editing over peer-to-peer networks.

Andrew Adams, a Halide developer, presents the Halide language for image processing and tensor computation. The talk explains the separation of algorithm from schedule with illustrated examples of parallelism, locality and redundancy tradeoffs.

Stephan T. Lavavej's CppCon 2019 talk on implementing floating-point to_chars and from_chars in Microsoft's C++ STL. It covers the history of float-string conversion and the algorithms that make it much faster.

Martin Kleppmann surveys current research on CRDTs, the algorithms for merging concurrent edits across offline replicas. He covers the hard parts such as rich text, moves and merge results that are technically correct but poor.

A long live-coded DJ set in which Sam Aaron creates all the music in real time by writing code in his Sonic Pi system. It demonstrates algorithmic electronic music performance.

Neil Fraser of Google presents Differential Synchronization, the algorithm behind MobWrite, for keeping multiple copies of a document in sync in real time. The talk argues the approach is robust, convergent and efficient.

Guy Steele's Strange Loop 2010 talk argues that programmers should not have to think about parallelism, and that languages should support algorithms built on independence and divide-and-conquer. He also recounts fitting a program onto a single punch card.

Martin Kleppmann's Strange Loop talk on database transactions, covering why they were dropped by NoSQL, their reputation for being slow, and newer algorithms that make serializable transactions perform and scale. It touches on consistency, linearizability and the CAP theorem.

Andrei Alexandrescu's ACCU 2016 talk previews material from his book on writing fast code, with a focus on optimization techniques such as sentinels and faster search.

Rick Falkvinge responds to viewer feedback on his earlier Lightning Network video and raises a flaw he says was not previously discussed. The main thread is the network's unsolved routing problem.

A 1999 Qwest commercial in which a weary traveler at a remote motel is told every room offers every movie ever made, on demand. It was shot at Roy's Motel in Amboy, California.