"All ages"--Page 4 of Cover.

Different types of knots -- Cloud classification -- The solar system -- Anatomy of type -- The human skeleton -- Spelling, Morse, and semaphore alphabets -- Atomic structure -- The golden ratio & the Fibonacci sequence -- Music notation -- The anatomy of a bicycle -- The structure & atmosphere of planet Earth -- Greek alphabet -- Screws & nails -- Impossible shapes -- Time zones & tectonic plates -- The human eye -- Ship's watch schedule & international code of signals -- Flight -- Solstices and equinoxes -- Rivers -- Periodic table of the elements -- Pencils & brushes for the artist and designer -- The phases of the moon -- Organs of the body -- Regular polygons -- The layout of an orchestra -- Neap & spring tides -- Roman numerals -- The Mohs scale of mineral hardness -- International Organization for Standardization paper sizes.

Facts and figures for the curious reader. Covers more than 30 fascinating "general knowledge" topics, including shapes, tides, the solar system, and the periodic table.