This art history video discussion examines Baron Antoine-Jean Gros's "Napoleon Bonaparte Visiting the Plague-Stricken in Jaffa", 1804, oil on canvas (Musج©e du Louvre, Paris).

This art history video discussion examines Guercino's St. Luke Displaying a Painting of the Virgin, oil on canvas, 1652-53 (Nelson-Atkins Museum of Art, Kansas City).

This art history video discussion examines Gustav Klimt's "Beethoven Frieze", Vienna Secession, 1902.

This art history video discussion examines Gustav Klimt's "The Kiss", 1907-8, oil and gold leaf on canvas, 180 x 180 cm (Osterreichische Galerie Belvedere, Vienna).

This art history video discussion examines Gustave Caillebotte's "Paris Street; Rainy Day", 1877, oil on canvas 83-1/2 x 108-3/4 inches / 212.2 x 276.2 cm (The Art Institute of Chicago).

This video provides a virtual tour of Hadrian's Villa using a 3D digital model of the villa created under the direction of Dr. Bernard Frischer. The ruins of Hadrian's Villa, in the town of Tivoli, near Rome, is spread over an area of approximately 250 acres. Many of the structures were designed by the Emperor Hadrian who ruled from 117 until his death in 138 C.E. This virual rendering is based on current archeological research and has been created in consultation with art historians, archaeologists, and museum curators with expertise in this area. Please note, a few features are necessarily assumptions based on the best available evidence.

This art history video discussion examines Frans Hals' "Singing Boy with Flute", c. 1623, oil on canvas (Gemaldegalerie, Staatliche Museen zu Berlin).

This art history video discussion examines Frans Hals's "Malle Babbe", c. 1633, oil on canvas, 78.50 x 66.20 cm (Gemaldegalerie, Staatliche Museen zu Berlin).

Although mom controls the oxygen source, the fetus has a couple of clever tricks to get the most oxygen possible! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Learn how the needs of the fetus are met by the placenta, which is a special organ that belongs to both the mother and the fetus! Rishi is a pediatric infectious disease physician and works at Khan Academy.

Using the stethoscope to check blood pressure is a technique thatپگs been used for >100 years! Blood pressure is one of the major vital signs frequently measured by health care workers, and it tells us a lot about our blood circulation. Learn what blood pressure is, how it relates to resistance in a tube, why it is necessary to get oxygen to your cells, and how it can change as you age. Weپگll finally put it all together by relating pressure, flow, and resistance in one awesome equation!

No organ quite symbolizes love like the heart. One reason may be that your heart helps you live, by moving ~5 liters (1.3 gallons) of blood through almost 100,000 kilometers (62,000 miles) of blood vessels every single minute! It has to do this all day, everyday, without ever taking a vacation! Now that is true love. Learn about how the heart works, how blood flows through the heart, where the blood goes after it leaves the heart, and what your heart is doing when it makes the sound پàLub Dubجز.

Every time you take a breath, oxygen makes it way into your lungs. Follow along on that journey! Rishi is a pediatric infectious disease physician and works at Khan Academy.

This art history video discussion looks at Eva Hesse's "Untitled (Rope Piece)", 1970, rope, latex, string, wire, variable dimensions (Whitney Museum of American Art).

This art history video discusses the Damien Hirst sculpture, "The Physical Impossibility of Death in the Mind of Someone Living," and issues of interpretation.

This art history video discusses the Historiated capitals from the crossing of the Church of Sant Miquel of the castle of Camarasa (Noguera), early 13th century, stone, 77 x 1.65 x 77.5 cm (Museu Nacional d'Art de Catalunya, Palau Nacional, Barcelona).

In this 14-minute video lesson, Sal gives an overview of the cycles of regulation, de-regulation and government in 20th century US capitalism. [History playlist: Lesson 13 of 26]

In this 15-minute video lesson Sal gives an outline of the 1973 Allende Coup in Chile and Pinochet's Junta. [History playlist: Lesson 11 of 26]

This 6-minute video lesson looks at the American Civil War from from Lee's Surrender to Grant to Lincoln's Assassination. [History playlist: Lesson 2 of 26]

This 14-minute video lesson discusses the Bay of Pigs Invasion. [History playlist: Lesson 7 of 26]