  The World Wide Web continues to evolve and serve as the infrastructure for
carrying massive amounts of multimodal and multisensory observations. These
observations capture various situations pertinent to people's needs and
interests along with all their idiosyncrasies. To support human-centered
computing that empower people in making better and timely decisions, we look
towards computation that is inspired by human perception and cognition. Toward
this goal, we discuss computing paradigms of semantic computing, cognitive
computing, and an emerging aspect of computing, which we call perceptual
computing. In our view, these offer a continuum to make the most out of vast,
growing, and diverse data pertinent to human needs and interests. We propose
details of perceptual computing characterized by interpretation and exploration
operations comparable to the interleaving of bottom and top brain processing.
  This article consists of two parts. First we describe semantic computing,
cognitive computing, and perceptual computing to lay out distinctions while
acknowledging their complementary capabilities. We then provide a conceptual
overview of the newest of these three paradigms--perceptual computing. For
further insights, we focus on an application scenario of asthma management
converting massive, heterogeneous and multimodal (big) data into actionable
information or smart data.
