This book is motivated by stimulating problems in contact mechanics,
emphasizing antiplane frictional contact with linearly elastic and
viscoelastic materials. It focuses on the essentials with respect to the
qualitative aspects of several classes of variational inequalities
(VIs). Clearly presented, easy to follow, and well-referenced, this work
treats almost entirely VIs of the second kind, with much of the material
being state-of-the-art.