Credits & Licenses

All article titles, summaries and encyclopedic text shown in Erask come from Wikipedia, the free encyclopedia, and are written by its volunteer contributors.

Text is available under the Creative Commons Attribution-ShareAlike 4.0 license. Each article in the app links directly to its original Wikipedia page, where the full text and the complete list of authors can be found.

The structured facts that power Erask’s exploration — coordinates, categories (castle, battlefield, monastery…), dates of founding, birth and death, and the references that connect one article to another — come from Wikidata, the free knowledge base. The globe does not query them live: Erask reads the full public dump once, keeps the handful of properties it needs, and ships the result as a single file. The connections between entries are Wikidata’s own part of and participant statements, written in both directions so a war knows its battles and a battle knows its war; the family view of an area uses part of alone. The story editor and stories written with a language model are the exception: they look their articles up on Wikidata when you open them.

Wikidata’s data is released under Creative Commons CC0 1.0 (public domain dedication).

The photographs shown with each article in Erask are hosted on Wikimedia Commons, the free media repository, and were created by thousands of photographers who chose to share their work.

Each file on Commons carries its own free license (typically Creative Commons or public domain) and attribution. Every photo in the app sits beside a link to its Wikipedia article, from which the file’s page on Commons — with its author and exact license — is one click away.

The names on the globe — the cities, and which of them appear at which zoom — come from Natural Earth, a public-domain map dataset built through a collaboration of volunteer cartographers.

The surface of the globe is a photograph of the Earth: Blue Marble Next Generation, assembled by NASA’s Earth Observatory from a year of MODIS observations and published at 463 metres per pixel. It arrives as eight tiles of 21600×21600 pixels; we cut it into a pyramid of five levels so that the browser only downloads the piece you are looking at. Its own colours are left alone — the ochre of the Sahara and the green of the Amazon are the ones the satellite recorded, not a palette chosen to match this interface.

The 3D mountain relief on the globe is rendered from Shuttle Radar Topography Mission (SRTM) elevation data, processed by Reto Stockli, NASA Earth Observatory. NASA imagery and data are in the public domain.