# Colloquium abstracts

**Paul Baum**

University of Penn State, USA

February 28, 2013

**What is K-Theory and what is it good for?**: This talk consists of four points. 1. The basic definition of K-theory 2. A brief history of K-theory 3. Algebraic versus topological K-theory 4. The unity of K-theory The talk is intended for non-specialists. Only a general mathematical background will be assumed.