October 19, 2026
The Map Before the Emergency: How Volunteers Add Missing Roads and Buildings
Humanitarian mapping volunteers trace roads and buildings from satellite imagery, helping create open map data that aid groups and communities…
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Documents & Reference
October 19, 2026
From a Paris Standard to the SI: A Timeline of the Metric System
The metric system began as a French effort to replace a patchwork of local measures. Its evolution—from a proposed Earth-based…
October 19, 2026
How the UN Counts the World’s Population Without a Global Census
There is no single worldwide head count. The UN combines national censuses, surveys and other records to estimate how many…
October 19, 2026
The 1507 Map That Put “America” on the World
A large woodcut map made in Europe gave a newly recognized landmass a name that endured. Its story is less…
October 19, 2026
How to Read a Library of Congress Call Number: A Shelf-Finding Guide
A call number is more than a book’s address. Learn what its parts can tell you, how to follow it…
October 17, 2026
The 1950 Census Is Open: How a 72-Year Rule Turns a Snapshot Into a Record
The 1950 U.S. census is now available to the public, offering a detailed snapshot of households and communities—while illustrating why…
October 17, 2026
The Homestead Act: A Promise of Land Written Into Federal Law
Signed in 1862, the Homestead Act offered a path to land ownership—but its requirements, and the meaning of “public land,”…
October 17, 2026
GNIS: The U.S. Place-Name Directory Behind the Map
The Geographic Names Information System helps users identify and compare names for places and features across the United States. Its…
October 17, 2026
911 in the United States: A Timeline From First Call to Next Generation
The U.S. emergency number began as a proposal for one memorable way to call for help. Its history shows how…
October 16, 2026
The Domesday Book: How a Medieval Survey Made England Legible to Its Rulers
Ordered by William the Conqueror and compiled in 1086, the Domesday survey turned land, ownership and resources into a record…
October 16, 2026
The ISBN: How a Numbering System Made Books Easier to Find
A book’s ISBN is more than a barcode: it is a standardized identifier that helps publishers, booksellers, libraries and readers…
October 16, 2026
The Rosetta Stone: The Decree That Helped Make Ancient Egyptian Legible Again
A broken slab bearing one decree in three scripts gave scholars a crucial way into ancient Egyptian writing—and the key…
October 16, 2026
The ICD: How a Global Medical Classification Makes Health Data Comparable
The International Classification of Diseases gives health systems a shared way to describe conditions and record causes of death—while leaving…
October 16, 2026
Unicode: The Shared Character Standard That Helps Text Travel Around the World
A letter, a symbol or an emoji can look simple on screen. Behind it is a shared system that helps…
October 16, 2026
WoRMS: The Ocean-Life Directory That Helps Scientists Agree on Names
The World Register of Marine Species is more than a searchable list. Its expert-maintained records help researchers connect ocean-life data…
October 16, 2026
GBIF: The Global Directory That Shows Where Life Has Been Recorded
A worldwide network of museums, research institutions and community science projects shares biodiversity observations through GBIF, giving researchers a way…
October 16, 2026
IFLA’s Library Map of the World: A Global Directory That Makes Libraries Visible
A country-by-country resource from the International Federation of Library Associations and Institutions brings library statistics and community stories into one…
October 16, 2026
DOAJ: The Directory That Helps Readers Find Open-Access Journals
The Directory of Open Access Journals began as a way to make scholarly research easier to find. Its lasting value…
October 16, 2026
UNESCO’s World Heritage List: A Global Directory With a Duty to Protect
The World Heritage List is more than a catalogue of famous places. It connects sites around the world through shared…
October 14, 2026
The Federal Register: How a Daily Government Journal Made Rules Public
A 1935 law created a shared public record for U.S. government rules, notices and presidential documents. The Federal Register still…