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Main content

Science

Health and medicine

The medical world can be a confusing place. Patients, their families, and even students entering health fields might feel overwhelmed by the large vocabularies and complicated explanations. We hope to make understanding the medical world a bit easier. Look around! These videos do not provide medical advice and are for informational purposes only. The videos are not intended to be a substitute for professional medical advice, diagnosis or treatment. Always seek the advice of a qualified health provider with any questions you may have regarding a medical condition. Never disregard professional medical advice or delay seeking it because of something you have read or seen in any Khan Academy video.

Cosmology and astronomy

It's a great, big universe out there. In this section of Khan Academy, you'll learn about the brain-bending vastness of time and space. We go from plate tectonics here on Earth to entire galaxies and beyond.