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Interactive history and timelines

Explore events on a calendar, move through cosmic time, or trace a programming tradition. Each experience offers a different way to put events and ideas in context.

Choose a way to explore

Explore a date or a span of time

This Day in History lets you choose a date and order events in a short challenge. Cosmic Time Machine places milestones on a much larger timeline. Hello World follows the first-program tradition across programming languages.

Follow the sources and context

This Day in History uses saved Wikipedia material and links to source articles. Its selection is not a complete record of every event. Follow the links for context, and read dates and early historical interpretations with the source’s conventions in mind.