  Human motion analysis and understanding has been, and is still, the focus of
attention of many disciplines which is considered an obvious indicator of the
wide and massive importance of the subject. The purpose of this article is to
shed some light on this very important subject, so it can be a good insight for
a novice computer vision researcher in this field by providing him/her with a
wealth of knowledge about the subject covering many directions. There are two
main contributions of this article. The first one investigates various aspects
of some disciplines (e.g., arts, philosophy, psychology, and neuroscience) that
are interested in the subject and review some of their contributions stressing
on those that can be useful for computer vision researchers. Moreover, many
examples are illustrated to indicate the benefits of integrating concepts and
results among different disciplines. The second contribution is concerned with
the subject from the computer vision aspect where we discuss the following
issues. First, we explore many demanding and promising applications to reveal
the wide and massive importance of the field. Second, we list various types of
sensors that may be used for acquiring various data. Third, we review different
taxonomies used for classifying motions. Fourth, we review various processes
involved in motion analysis. Fifth, we exhibit how different surveys are
structured. Sixth, we examine many of the most cited and recent reviews in the
field that have been published during the past two decades to reveal various
approaches used for implementing different stages of the problem and refer to
various algorithms and their suitability for different situations. Moreover, we
provide a long list of public datasets and discuss briefly some examples of
these datasets. Finally, we provide a general discussion of the subject from
the aspect of computer vision.
