Since the work of Stasheff and Sugawara in the 1960s on recognition of loop space structures on $H$-spaces, the notion of higher homotopies has grown to be a fu

The main theme of this book is that the use of filtered spaces rather than just topological spaces allows the development of basic algebraic topology in terms o

The study of higher categories is attracting growing interest for its many applications in topology, algebraic geometry, mathematical physics and category theor