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About

Since 1994, Quatr.us Study Guides has offered free history and science articles to keep you connected to the latest discoveries in world history. We want you to know why things happened, how that matters today, and what you can do about it. Experts write all our 2500 articles (and counting!), with full bibliography and citation information. Coming soon: free lesson plans and a first-rate resource area.

Why are we called Quatr.us?

Good question! We were thinking of the four corners of the world - four Quarters. We were thinking of Questions, and Quick, and Quality. We wanted a name that would be ours and nobody else's.

Get in touch!

We’d love to talk! Reach out on twitter (@Quatr_us) or Instagram (@quatr.us) or by email (karen @ quatr.us). Open to your sponsorships, link exchanges, or just friendly talk about history. I’d be up for guest posts on your blog, joint Twitter threads, lesson plans, book reviews, or what-have-you. Send all your ideas!

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