Course description for MATH 517A, Group Theory, Fall 2004. Numerous problems of the natural and technical sciences possess certain symmetry properties. If we manage to understand them, then a mathematical treatment adjusted to the symmetry properties lead to a considerable simplification. In this course on group theory, the main emphasis will be on this connection. We will develop the basics of group theory and then apply them to study a variety of applications. The most important tool that allows us to study symmetries via group theory is covered by the theory of realizations of groups as matrices, also called representation theory of groups. We will therefore start with studying representation theory using the book ``Groups and characters`` by L. Grove. Moreover, we will look at applications from A. Terras book on Fourier analysis on finite groups. The examples discussed there cover applications of groups to graph theory, coding theory, statistics and probability theory. If time permits we are also going to look at problems from combinatorics, algebraic topology, number theory and other areas. Since examples are an important part of any mathematical theory, I will offer introductions on how to use various computer algebra systems such as GAP, Maple, and others, to study symmetries in concrete situations. The main prerequisite for this course is the core algebra course 511A/B.