Abstract
An affine arrangement of hyperplanes is a finite collection of one-codimensional affine linear spaces in ${C}^n$. P. Orlik and H. Terao are leading specialists in the theory of arrangements and the co-authors of the well-known book "Arrangements of Hyperplanes." In this monograph, they give an introductory survey which also contains the recent progress in the theory of hypergeometric functions. The main argument is done from the arrangement-theoretic point of view. This will be a nice text for a student to begin the study of hypergeometric functions.