"Sculpture is the branch of the visual arts that operates in three dimensions" Wikipedia, July 2014
Until the digital era, sculptures had to be created using real matter. The advent of digital tools gave rise to a new art: virtual sculptures.
A virtual sculpture is a digital file and has no material presence. Such sculpture cannot be touched, nor be placed on a table or erected in a town square. It can be, however, (virtually) photographed, and one can have the picture printed and viewed. Recent technological advances allow a conversion from a virtual sculpture to a material one, using special 3D printing machines.
Real sculpturing requires a studio, tools and materials. None of these are needed for virtual sculpturing; a desk with a computer is all that is required. Virtual sculpturing does not give rise noise or dirt, and can be practiced anytime and everywhere.
The creation process in the digital realm is free from limtations imposed by work with real materials. The artist can suspend his work at any instant; when the work is resumed, he finds it in exactly the same state as he left it. His materials do not dry out or expire, and his tools do not wear out. In virtual sculpturing there are no critical decisions: any step can be "undone". The digital artist, freed from the burden and anxiety of making irreversible decisions, can focus all his creative energy in his art.
Credit: picture based on Jesse's "Pearl" design (Fractal Forums)