Calder's cutting-edge work transformed modern art in the twentieth century. As a young man, Calder mastered the wire sculpture, which he describes as thus, according to a statement published by the Calder Foundation:
I did not consider this medium to be of any signal importance in the world of art; merely a very amusing stunt cleverly executed. [...] Before, [my] wire studies were subjective, portraits, caricatures, stylized representations of beasts and humans. But these recent things have been viewed from a more objective angle and although their present size is diminutive, I feel that there is no limitation to the scale to which they can be enlarged.
As a more mature artist, his understanding of the effects of multiple viewpoints on a single piece of work led him to invent a dynamic kind of hanging sculpture with weighted parts that moved and transformed the piece, depending on the observer's angle of view. These mobiles hang in a variety of galleries across the world, including the National Gallery of Art in the United States.
The logo on Google.com has been replaced with a digital representation of a Calder mobile, whose colorful weights rotate slowly when a Googler clicks and drags on a part of the sculpture.
This Google doodle also has a hands-free feature. CNET notes that the user can tip or tilt an accelerometer-equipped laptop to make the logo spin.