May 1967
Object-oriented programming invented
In May 1967, Ole-Johan Dahl and Kristen Nygaard presented classes and inheritance at a simulation conference in Oslo — the birth of object-oriented programming.
What it was for
SimulaAn early language that introduced objects and classes — a direct ancestor of object-oriented programming. 67 bundled data and behavior into reusable 'objects' that could inherit from each other — the ideas behind C++, JavaA portable language running on the JVM — dominant in enterprise servers, Android, and big data., PythonA high-level language known for readability — dominant in data science, scripting, and web backends. classes, and most modern app design. It was built to model real-world systems like factory queues and traffic, but the object model outlived simulation.
People
- Ole-Johan Dahl — creator
- Kristen Nygaard — co creator
Why it's here
This is the moment object-oriented programming became a language feature — not just a design pattern in someone's head.
Why it mattered
Classes let developers model real things (accounts, vehicles, users) once and reuse that structure everywhere — every major language copied this.
What it solved
Simulation software needed reusable models of entities (customers, machines, vehicles) without rewriting the same logic for every project.
Media
- ImageSimula logo
Norwegian Computing Center, public domain, via Wikimedia Commons
Related
- ALGOL 60 language definedMay 1, 1960