City systems

Civilization Museum · 06

Mathematics, Computing & Information

From algorithms, logic, and programs to databases, networks, cryptography, and the Web, this wall follows how cats wrote problems as rules, let machines execute them, and learned to organize, transmit, and protect information.

Writing Problems as Rules

Al-Khwarizmi Cat arranges a complex problem into a sequence of algorithmic steps.
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Al-Khwarizmi Cat

Al-Khwarizmi Cat organized complex calculations into clear, sequential steps that could be checked and repeated. An algorithm gives not only an answer, but also a method for reaching it.

Leibniz Cat operates a mechanical calculator while arranging black-and-white binary counters.
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Leibniz Cat

Leibniz Cat explored binary notation, symbolic calculation, and mechanical calculating devices, imagining that clear rules could be carried out by machines. His ideas opened an early path toward representing complex computation with simple symbols.

Boole Cat changes logic switches and observes the resulting output.
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Boole Cat

Boole Cat turned logical relations such as AND, OR, and NOT into an algebra that could be calculated. Logic could now enter switches, circuits, and digital computation as well as reasoning.

What Machines Can Do

Ada Lovelace Cat places a punched card into an Analytical Engine model while reviewing an algorithm.
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Ada Lovelace Cat

Building on Babbage Cat’s Analytical Engine design, Ada Cat wrote and explained ways for a machine to carry out complex sequences. She also saw that general-purpose computation might work with symbols, patterns, and music, not numbers alone.

Turing Cat feeds a paper tape through a machine head while checking a state-transition diagram.
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Turing Cat

Turing Cat studied which tasks can be completed by explicit rules and showed that some problems have no mechanical solution. Machines can do a great deal, but computation itself has limits.

John von Neumann Cat places program and data cards into the same stored-program model.
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John von Neumann Cat

With mathematicians and engineers in early computer projects, von Neumann Cat helped develop systems in which programs and data could be stored within the same machine. Computers could then read, modify, and execute different programs more flexibly.

Grace Hopper Cat feeds a high-level program card into a compiler and receives machine instructions.
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Grace Hopper Cat

Hopper Cat advanced compilers and higher-level programming languages so cats would not always have to write a machine’s lowest-level instructions directly. Programs could describe the problem more closely and be translated for the machine.

Organizing Information

Shannon Cat compares an encoded signal before and after noise in a communications laboratory.
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Shannon Cat

Shannon Cat studied how information can be measured, encoded, and transmitted reliably through noise. Even when communication is disturbed, suitable encoding and checking can help a message arrive correctly.

Edgar Codd Cat connects related data cards and uses a query card to retrieve a result.
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Edgar Codd Cat

Codd Cat proposed organizing data by relations so records could be queried, combined, and maintained through clear structures. Data no longer had to remain trapped inside one program or file arrangement.

Connecting, Transmitting & Protecting

Vint Cerf Cat connects two differently structured network modules through a shared protocol path.
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Vint Cerf Cat

Cerf Cat, Bob Kahn Cat, and other researchers advanced internetworking protocols that let structurally different networks exchange data through shared rules. The Internet is not one network, but a connection among many networks.

Whitfield Diffie Cat sends a public parameter card and forms a secret key in an open-network experiment.
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Whitfield Diffie Cat

Diffie Cat, Hellman Cat, and Merkle Cat advanced key ideas in public-key cryptography, allowing parties without a previously shared secret to establish secure communication over an open network. Open connection could now preserve privacy and trustworthy identity.

Tim Berners-Lee Cat connects two document nodes in an open Web workspace.
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Tim Berners-Lee Cat

Berners-Lee Cat used URLs, HTTP, HTML, and open standards to connect scattered documents into the browsable World Wide Web. Networks became not only a way to transmit data, but a linked space through which residents could share knowledge.