# computerscience.co.uk > The history of computer science, the people who built it, and rankings of the > best places to study it. Every fact is sourced; every page shows the date it was > last reviewed. Every HTML page has a markdown twin: append `index.md` to any > URL path, or request any page with `Accept: text/markdown`. The whole site is also an Open Knowledge Format (OKF v0.1) bundle rooted at [/index.md](https://computerscience.co.uk/index.md), made of markdown documents with YAML frontmatter, cross-linked into a knowledge graph. ## Sections - [The history of computer science](https://computerscience.co.uk/history/index.md): eras, machines and breakthroughs, plus direct answers to common questions - [The people](https://computerscience.co.uk/people/index.md): sourced biographies of the field's key figures - [The universities](https://computerscience.co.uk/universities/index.md): global CS rankings aggregated from QS, THE, ARWU and CSRankings - [The unsolved problems](https://computerscience.co.uk/challenges/index.md): famous open problems of computer science, each with an interactive demo you can try in the browser ## People - [Ada Lovelace: the First Computer Programmer](https://computerscience.co.uk/people/ada-lovelace/index.md): Ada Lovelace wrote what is considered the first computer program in 1843 and saw that a machine could do more than arithmetic, long before any computer existed. - [Alan Turing: the Founder of Computer Science](https://computerscience.co.uk/people/alan-turing/index.md): Alan Turing defined the computer in 1936, helped break German ciphers in the Second World War, and set the terms for artificial intelligence. - [Charles Babbage: the Father of the Computer](https://computerscience.co.uk/people/charles-babbage/index.md): Charles Babbage designed the Difference Engine and the Analytical Engine in the 1800s, laying out the shape of the general-purpose computer a century early. - [Claude Shannon: the Father of Information Theory](https://computerscience.co.uk/people/claude-shannon/index.md): Claude Shannon founded information theory, the mathematics behind all digital communication, and showed that logic could be built from electrical switches. - [Donald Knuth: the Author of The Art of Computer Programming](https://computerscience.co.uk/people/donald-knuth/index.md): Donald Knuth turned programming into a rigorous science through The Art of Computer Programming, and created the TeX system that typesets much of the world's science. - [Dennis Ritchie: Creator of C and Co-Creator of Unix](https://computerscience.co.uk/people/dennis-ritchie/index.md): Dennis Ritchie created the C programming language and co-created Unix, two foundations that almost all modern software is still built on. - [Edsger Dijkstra: the Conscience of Programming](https://computerscience.co.uk/people/edsger-dijkstra/index.md): Edsger Dijkstra gave computer science its most famous shortest-path algorithm and argued that programming should be a rigorous, disciplined craft. - [Grace Hopper: the Programmer Who Made Code Readable](https://computerscience.co.uk/people/grace-hopper/index.md): Grace Hopper built the first compiler and helped create COBOL, turning programming from raw machine code into something written in words. - [John von Neumann: Architect of the Modern Computer](https://computerscience.co.uk/people/john-von-neumann/index.md): John von Neumann set out the stored-program design used by almost every computer since, and did foundational work across mathematics, physics and game theory. - [Guido van Rossum: the Creator of Python](https://computerscience.co.uk/people/guido-van-rossum/index.md): Guido van Rossum created Python, the programming language that became the default for teaching, data science and artificial intelligence. - [Linus Torvalds: the Creator of Linux](https://computerscience.co.uk/people/linus-torvalds/index.md): Linus Torvalds created Linux, the operating system that runs most of the internet, and Git, the version control system used across software today. - [Tim Berners-Lee: the Inventor of the World Wide Web](https://computerscience.co.uk/people/tim-berners-lee/index.md): Tim Berners-Lee invented the World Wide Web in 1989 at CERN, giving the internet the pages, links and browsers that turned it into something everyone could use. - [Vint Cerf: a Father of the Internet](https://computerscience.co.uk/people/vint-cerf/index.md): Vint Cerf co-designed TCP/IP, the protocols that let separate networks join into one internet, which is why he is called a father of the internet. ## History - [A timeline of computer science](https://computerscience.co.uk/history/timeline/index.md): key dates from Babbage to modern AI - [The Foundations of Computer Science](https://computerscience.co.uk/history/foundations/index.md): In the 1930s and 1940s, Turing, Shannon and von Neumann turned computing into a science, defining what machines could compute and how to build them. - [The Internet Age](https://computerscience.co.uk/history/internet-age/index.md): From ARPANET in 1969 to the World Wide Web and beyond, computing became a global network that reshaped how people work, talk and live. - [The Mechanical Age of Computing](https://computerscience.co.uk/history/mechanical-computing/index.md): Before electronics, computing was mechanical. Babbage's engines and Lovelace's programs imagined the general-purpose computer a century before it could be built. - [The Rise of Programming Languages](https://computerscience.co.uk/history/programming-languages/index.md): As computers spread in the 1950s and 1960s, Grace Hopper and others made them programmable in something closer to human language, from the first compiler to COBOL. - [What Is a Turing Machine?](https://computerscience.co.uk/history/turing-machine/index.md): A Turing machine is a simple imaginary device, described by Alan Turing in 1936, that captures what it means to compute and underpins all of computer science. - [What Is Computer Science?](https://computerscience.co.uk/history/what-is-computer-science/index.md): Computer science is the study of computation: how problems are solved by algorithms, how information is processed, and how hardware and software are designed. - [When Was the First Computer Invented?](https://computerscience.co.uk/history/when-was-the-first-computer-invented/index.md): The first computer was designed in the 1830s by Charles Babbage. The first working electronic computers were built in the 1940s, with ENIAC completed in 1945. - [Who Invented the Computer?](https://computerscience.co.uk/history/who-invented-the-computer/index.md): No single person invented the computer. Charles Babbage designed the first general-purpose computer in the 1800s, and working electronic computers arrived in the 1940s. - [Who Invented the Internet?](https://computerscience.co.uk/history/who-invented-the-internet/index.md): The internet grew from ARPANET in the 1960s, with core protocols by Vint Cerf and Bob Kahn. The World Wide Web that runs on it was invented by Tim Berners-Lee in 1989. ## Universities - [University of Birmingham](https://computerscience.co.uk/universities/birmingham/index.md): Birmingham was the first English redbrick university with its own royal charter; its School of Computer Science spans AI, robotics, security and theory. - [California Institute of Technology (Caltech)](https://computerscience.co.uk/universities/caltech/index.md): Caltech is a small, elite science university in California whose computing and mathematical sciences are among the most selective and rigorous anywhere. - [University of Cambridge](https://computerscience.co.uk/universities/cambridge/index.md): Cambridge taught the world's first university course in computing and remains one of the strongest computer science departments in the United Kingdom. - [Carnegie Mellon University](https://computerscience.co.uk/universities/carnegie-mellon/index.md): Carnegie Mellon ranks in the top ten worldwide for computer science and runs one of the few universities with a full school devoted to the subject. - [Cornell University](https://computerscience.co.uk/universities/cornell/index.md): Cornell University is a top US computer science department, an Ivy League university strong across systems, theory and artificial intelligence. - [ETH Zurich](https://computerscience.co.uk/universities/eth-zurich/index.md): ETH Zurich is one of Europe's leading universities for computer science, a Swiss public institution strong across systems, machine learning and robotics. - [Harvard University](https://computerscience.co.uk/universities/harvard/index.md): Harvard University is one of the world's most famous universities, with a strong and fast-growing computer science programme inside its school of engineering. - [Imperial College London](https://computerscience.co.uk/universities/imperial-college-london/index.md): Imperial College London is a top-25 computer science university worldwide in the QS 2026 rankings, and one of the UK's strongest for science and engineering. - [Massachusetts Institute of Technology (MIT)](https://computerscience.co.uk/universities/mit/index.md): MIT is ranked first in the world for computer science in the QS 2026 subject rankings. A look at why, and what studying CS there involves. - [National University of Singapore (NUS)](https://computerscience.co.uk/universities/nus/index.md): The National University of Singapore is ranked joint fourth in the world for computer science by QS in 2026, the top-ranked department in Asia. - [University of Oxford](https://computerscience.co.uk/universities/oxford/index.md): Oxford is ranked joint fourth in the world for computer science in the QS 2026 subject rankings, the top-ranked department in the United Kingdom. - [Princeton University](https://computerscience.co.uk/universities/princeton/index.md): Princeton University is one of the leading US computer science departments, known for particular depth in the theory of computation and algorithms. - [Queen's University Belfast](https://computerscience.co.uk/universities/queens-belfast/index.md): Queen's University Belfast, chartered in 1845, hosts CSIT, the UK's national innovation centre for cyber security and a GCHQ-recognised research hub. - [University of Southampton](https://computerscience.co.uk/universities/southampton/index.md): Southampton pioneered Web Science and houses Electronics and Computer Science (ECS), where web inventor Tim Berners-Lee joined the faculty in 2004. - [Stanford University](https://computerscience.co.uk/universities/stanford/index.md): Stanford sits in the top ten worldwide for computer science in the QS 2026 rankings, and its place in Silicon Valley has shaped the whole industry. - [University of Sussex](https://computerscience.co.uk/universities/sussex/index.md): Sussex was the first of Britain's plate glass universities, chartered in 1961; its Department of Informatics is strong in AI, robotics and HCI. - [University of Toronto](https://computerscience.co.uk/universities/toronto/index.md): The University of Toronto is Canada's leading university for computer science and a birthplace of the modern deep learning revolution in artificial intelligence. - [University of California, Berkeley](https://computerscience.co.uk/universities/uc-berkeley/index.md): UC Berkeley is one of the world's leading computer science departments and a public university whose research shaped Unix, databases and processor design. - [Best Computer Science Universities in the UK](https://computerscience.co.uk/universities/united-kingdom/index.md): The top computer science universities in the UK, led by Oxford, Cambridge and Imperial College London, with sourced rankings and profiles. - [Best Computer Science Schools in the United States](https://computerscience.co.uk/universities/united-states/index.md): The top computer science schools and colleges in the US, from MIT and Stanford to Carnegie Mellon and Berkeley, with sourced rankings and profiles. ## Study - [Studying computer science](https://computerscience.co.uk/study/index.md): guides to CS degrees, careers, salaries and master's programmes ## Challenges - [The Busy Beaver Problem](https://computerscience.co.uk/challenges/busy-beaver/index.md): Why the busy beaver function defeats every algorithm, how BB(5) = 47,176,870 was finally proved in 2024, and a demo that runs the record machines in your browser. - [Can You Break Bitcoin's Cryptography?](https://computerscience.co.uk/challenges/breaking-bitcoin/index.md): SHA-256 and elliptic curve keys guard a trillion dollars of bitcoin. See why brute force fails, what quantum changes, and try cracking a toy key in your browser. - [The Collatz Conjecture](https://computerscience.co.uk/challenges/collatz-conjecture/index.md): The simplest unsolved problem in mathematics. Halve even numbers, triple odd ones and add one. Try any number in the demo and watch it fall to 1. - [The Graph Isomorphism Problem](https://computerscience.co.uk/challenges/graph-isomorphism/index.md): Same structure, different drawing: pair up the vertices yourself in the demo, then find out why nobody can solve graph isomorphism quickly, or prove that they cannot. - [The Halting Problem](https://computerscience.co.uk/challenges/halting-problem/index.md): The one challenge here that will never be solved. Turing proved in 1936 that no program can decide whether programs halt. Test yourself in the quiz. - [The Millennium Prize Problems](https://computerscience.co.uk/challenges/millennium-prize-problems/index.md): Seven problems named by the Clay Mathematics Institute in 2000, $1m each. One is solved, six are open, and P vs NP is the one computer science owns. - [One-Way Functions: The Bet All Cryptography Makes](https://computerscience.co.uk/challenges/one-way-functions/index.md): Multiplying two primes takes microseconds. Factoring the answer back has no known fast method, and nobody has proved one does not exist. - [P vs NP](https://computerscience.co.uk/challenges/p-vs-np/index.md): P vs NP asks whether every answer that is quick to check is also quick to find. Covers NP-complete problems, the $1m Clay prize, and a subset-sum demo to play. - [The Travelling Salesman Problem](https://computerscience.co.uk/challenges/travelling-salesman-problem/index.md): What the travelling salesman problem asks, why brute force fails, and how solvers cope. Includes an interactive demo where heuristics race through billions of routes. ## Reference - [HTTP status codes](https://computerscience.co.uk/reference/http-status-codes/index.md): the complete list, explained, with detail pages for 402 (payments, AI agents) and 429 (rate limiting) - [HTTP vs HTTPS: What Is the Difference?](https://computerscience.co.uk/reference/http-vs-https/index.md): HTTP sends pages in plain text; HTTPS encrypts them with TLS. What the S adds, what the padlock really means, and how to check any site with our free tool. - [HSTS: HTTP Strict Transport Security Explained](https://computerscience.co.uk/reference/hsts/index.md): HSTS tells browsers to use HTTPS only. What max-age, includeSubDomains and preload really do, the removal trap, and a free tool to check any site's HSTS setup. ## Data and tools - [Open datasets](https://computerscience.co.uk/data/index.md): the timeline, universities (with coordinates) and HTTP status codes as JSON, CC BY 4.0, stable URLs - [HTTP status & redirect checker](https://computerscience.co.uk/reference/http-status-checker/index.md): free API at GET https://computerscience.co.uk/api/check?url={url} returns the full redirect chain (per-hop status, latency, headers), a graded security-header report (parsed HSTS max-age/includeSubDomains/preload, nosniff, X-Frame-Options, Referrer-Policy, CSP), SEO signals and AI-agent readiness - Live status-code tester: GET https://computerscience.co.uk/status/{code} returns that real status code (200-599), with Retry-After on 429/503 and Location on 3xx ## Optional - [Are you an AI agent?](https://computerscience.co.uk/ai/index.md): how to consume this site, citation policy, contact - [Sitemap](https://computerscience.co.uk/sitemap-index.xml)