This page hosts information on Stephan Müller's talk "What is … the classifying space of a category?" at the "What is …?" seminar. The talk will take place on Friday, June 11, 4pm at HU, RUD 25 1.023.
I will describe an easy way to associate a (nice) topological space to a (small) category - its classifying space. Using homotopy theory we can discover Quillen's higher K-theories.