An atlas is a book that contains illustrations of maps, charts, plates and tables on any subject, such as geography, history, astronomy and anatomy. The term "atlas" comes from the Greek god Atlas, a Titan said to support the entire Earth on his shoulders. The modern term "atlas" was introduced between 1580 and 1590.
Hardbound atlases serve as large reference books with color illustrations. Softcover atlases are often guides taken on trips so maps can be utilized during travel. Online atlases offer interactive elements that allow users to zoom in, zoom out and plot routes from various points.
The earliest book of maps, "Geographia," was published by Greco-Roman geographer Claudius Ptolemy in the second century. Bound atlases date back to 1475 at the Library of Congress, and as of 2014, the research institution holds 47 of the 56 known copies of Ptolemy's masterpiece. Another rare volume at the Library of Congress is Johann Ruysch's atlas of 1507, which incorporates explorations of the New World.
Atlases that focus on human anatomy are often textbooks for medical students because of detailed illustrations. Some anatomical atlases feature cross sections of tissue and organs, whereas others focus on microscopic views of the human body. One example is "Atlas of Human Anatomy," which shows anatomical structures by functional systems, such as skeletal, circulatory, muscular and nervous.