The Pietà, a Renaissance masterpiece depicting the body of Jesus on his mother's lap, is the only work of any sort that Michelangelo ever signed. He later regretted what he considered an outburst of pride and vowed to never sign another work again.

Blobism or blobitecture is a type of wavy, curvy building design without traditional edges or traditional symmetric form. American-born architect Greg Lynn is credited with founding the movement in 1995 while experimenting with metaball graphical software to create digital designs. Blob architecture is unthinkable without computer-aided design programs. Architects derive the forms by manipulating the algorithms of the computer modeling platform.

One of the best known magazine illustrators of the 1920s, John Held Jr. was an American cartoonist, printmaker, and illustrator. His drawings defined the flapper era so well that many people are still familiar with Held's work today.

Leonardo's greatest triumph was the smile of the Mona Lisa, which he started working on in 1503 and continued laboring over nearly until his death 16 years later. His distinctive approach was to apply the glaze in extraordinarily thin strokes and then very slowly, over months and years, apply additional layer upon thin layer. The result is a masterpiece that invites and responds to human interactions--a smile that seems to react to our gaze.

Romanesque art is the art of Europe from approximately 1000 AD to the rise of the Gothic style in the 13th century. The preceding period is known as the Pre-Romanesque period.

Henri de Toulouse-Lautrec was a French painter and illustrator whose immersion in the colourful and theatrical life of Paris in the late 19th century allowed him to produce a collection of provocative images of the decadent life of those times. Among the well-known works that he painted for the Moulin Rouge and other Parisian nightclubs are depictions of the singer Yvette Guilbert, the outrageous La Goulue, and the dancer Jane Avril.

Bloom County is a comic strip by Berkeley Breathed which originally ran from December 8, 1980 to August 6, 1989. It examines events in politics and culture through the viewpoint of a fanciful small town in Middle America, where animals can talk and children often have the vocabularies of adults. It evolved from a comic strip known as The Academia Waltz that Breathed produced for a student newspaper while majoring in photojournalism at the University of Texas.

When the Mona Lisa was stolen from the Louvre in 1911, it caused a media sensation, and visitors queued for hours to see the vacant wall. The empty space it left behind actually attracted more visitors than the painting had!

The portrait of George Washington on the current U.S. one-dollar bill is actually an unfinished work by the artist Gilbert Stuart. It was painted in 1796, when the president was 64 years old.

A pentimento is an alteration in a painting, evidenced by traces of previous work, showing that the artist has changed his or her mind as to the composition during the process of painting. The word is Italian for repentance.