From Wikipedia:

Hieronymus Bosch, (latinized, actually Jheronimus Bosch; his real name Jeroen van Aken) (c. 1450 - August 9, 1516) [1] was a prolific Early Netherlandish painter of the fifteenth and sixteenth centuries. Many of his works depict sin and human moral failings. Bosch used images of demons, half-human animals and machines to evoke fear and confusion to portray the evil of man.[1] The works contain complex, highly original, imaginative, and dense use of symbolic figures and iconography, some of which was obscure even in his own time. He is said to have been an inspiration for the surrealist movement in the twentieth century.

Bosch produced several triptychs, works of three paintings on wooden panels that are attached to each other. Among his most famous is The Garden of Earthly Delights.[1] This triptych depicts paradise with Adam and Eve and many wondrous animals on the left panel, the earthly delights with numerous nude figures and tremendous fruit and birds on the middle panel, and hell with depictions of fantastic punishments of the various types of sinners on the right panel. When the exterior panels are closed the viewer can see, painted in grisaille, God creating the Earth.