From the Italian Government website:

The G20 logo project stems from a reflection on the famous drawing "The Vitruvian Man" by Leonardo da Vinci, a symbol of Humanism, the Renaissance and Italy in the world. In the G20 logo, the blue square is the representation of Italy, the gold circle symbolizes the globe and the movement of renewal.

The three letters that make up the G20 logotype recall and represent the typical forms of architecture and Italian lettering. A clear and highly recognizable composition that manages to condense over 2000 years of history in its elegance.

The "G" evokes the Italy of Imperial Rome and is inspired by the letters engraved in the base of the Trajan's Column, one of the symbolic monuments of the capital.

The "2" is a tribute to the excellence of Italian typography in the world, the Bodoni, a neoclassical font designed in 1798 by the well-known engraver Gian Battista Bodoni. It is characterized by the strong contrast between thick and thin lines, synonymous with elegance and harmony.

In the modernist "0" and in the rigorous geometry of the circle, the essence of rationalist thought and the artistic avant-garde, such as Futurism, which managed to give new life to contemporary visual culture, are distilled.