Primer

Learn how things work.

Short courses in physics, maths, chemistry, biology, computing, engineering and astronomy. Each one is a handful of sections you can finish in a sitting, with your progress saved as you go.

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Courses to get you started

Pick a course, open the first section, and your place is saved from there.

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How Primer works

  1. 1 Pick a course

    Browse the catalog or search for a topic. Every course's sections are listed up front, so you know what you'll learn.

  2. 2 Learn a section at a time

    Each section is short enough for one sitting, with worked examples and formulas typeset properly.

  3. 3 Pick up where you left off

    Your progress is saved to your account, so you can carry on from any device you sign in from.

Two plans. Pick one.

Start free. Upgrade when you want every course.

Free

$0 forever

Every free course, with your progress saved.

  • Every free course
  • Progress saved section by section
  • Formulas and code rendered properly
Start learning

Premium Every course

$20 / month

Every course in the catalog.

  • Every Premium course
  • Everything in Free
  • New courses the day they are published
  • Cancel any time

Frequently asked questions

Is Primer free?

Yes. Every course marked Free is free to take, with your progress saved, as long as you're signed in. Premium courses need the Premium plan.

What does Premium include?

Every course in the catalog, Free and Premium, including new courses the day they are published. It's a monthly subscription; the price is in the Pricing section above.

Do I need an account?

You can browse every course and its list of sections without one. To read a section and save your progress, sign in with your Yard account.

How is my progress saved?

Opening a section marks it in progress, and you mark it complete when you've finished. Both are saved to your account, so the course picks up where you left off on any device.

How do I cancel Premium?

From your Yard library, where your subscription is listed. Payments and cancellations are handled by Yard.

Who writes the courses?

The team that runs this Primer. They write and edit every course and section from Primer's admin panel.