This 18-minute video lesson provides an overview of the Vietnam War. [History playlist: Lesson 9 of 26]

In this 14-minute video lesson Sal weighs in on capitalism and his understanding of when capitalism can potentially undermine innovation, competition and merit. [History playlist: Lesson 12 of 26]

This art history video discusses Hannah Hoch's "Cut with the Kitchen Knife Dada Through the Last Weimar Beer-Belly Cultural Epoch of Germany", collage, mixed media, 1919-1920.

This art history video discusses Hans Holbein the Younger's "Christina of Denmark", Duchess of Milan, 1538, oil on oak, 179.1 x 82.6 cm (The National Gallery, London).

This art history video discusses Hans Holbein the Younger's "The Ambassadors", 1533, oil on oak, 207 x 209.5 cm (The National Gallery, London).

This art history video discusses Hans Holbein the Younger's "The Merchant Georg Gisze", 1532, oil on oak, 97.5 x 86.2 cm (Gemaldegalerie, Staatliche Museen zu Berlin).

This art history video discussion looks at the "Holy Thorn Reliquary" (made in Paris for Jean, Duc de Berry), c. 1390s, gold, enamel, ruby, pearl, sapphire, and rock crystal, 30 x 14.2 x 6.8 cm (British Museum, London).

This art history video discussion looks at Winslow Homer's "The Fog Warning (Halibut Fishing)", 1885, oil on canvas, 30-1/4 x 48-1/2 inches / 76.83 x 123.19 cm (Museum of Fine Arts, Boston).

This art history video discussion looks at Winslow Homer's "The Life Line", 1884, oil on canvas, 28-5/8 x 44-3/4 inches / 72.7 x 113.7 cm (Philadelphia Museum of Art).

This art history video discussion looks at Edward Hopper's "Nighthawks", 1942, oil on canvas, 84.1 x 152.4 cm / 33-1/8 x 60 inches (The Art Institute of Chicago).

This art history video discussion looks at a "House Altar" depicting Akhenaten, Nefertiti and Three of their Daughters, limestone, New Kingdom, Amarna period, 18th dynasty, c.1350 BCE (Agyptisches Museum/Neues Museum, Staatliche Museen zu Berlin).

This art history video discussion looks at Jan (and Hubert?) Van Eyck's "Ghent Altarpiece or The Adoration of the Mystic Lamb", tempera and oil on panel, (closed panels), Cathedral of Saint Bavo, Ghent, Belgium, completed 1432. Second Life correspondents Max Newbold and Sez Zabelin, discuss the closed Ghent Altarpiece (see the next video for a discussion of the open altarpiece) on the Vassar campus in Second Life.

This art history video is the second part of the discussion about Jan (and Hubert?) Van Eyck's "Ghent Altarpiece or The Adoration of the Mystic Lamb", tempera and oil on panel, (open panels), Cathedral of Saint Bavo, Ghent, Belgium, completed 1432.

This art history video discussion examines William Holman Hunt's "Claudio and Isabella", 1850, oil on mahogany (Tate Britain). From William Shakespeare's Measure for Measure, Act III, scene 1 (a room in a prison).

This art history video discussion looks William Holman Hunts "Our English Coasts ('Strayed Sheep')", 1852, oil on canvas, 432 x 584 mm (Tate Britain, London).

This art history video discussion looks William Holman Hunt's "The Awakening Conscience", 1853, oil on canvas, 762 x 559 mm (Tate Britain, London).

This 7-minute video lesson looks at 2010 IIT JEE Paper 1 Problem 39.

This 7-minute video lesson continues to look at 2010 IIT JEE Paper 1 Problem 39.

This 3-minute video lesson concludes the discussion of 2010 IIT JEE Paper 1 Problem 39.

This art history video discussion looks at an "Icon of the Triumph of Orthodoxy (Byzantine)", c. 1400, tempera and gold on wood, 39 cm x 31 cm (British Museum, London).