  This book has four chapters. In chapter one we just recall the notion of RD
codes, MRD codes, circulant rank codes and constant rank codes and describe
their properties. In chapter two we introduce few new classes of codes and
study some of their properties. In this chapter we introduce the notion of
fuzzy RD codes and fuzzy RD bicodes. Rank distance m-codes are introduced in
chapter three and the property of m-covering radius is analysed. Chapter four
indicates some applications of these new classes of codes.
