I will introduce Chern-Simons type field theories in dimensions 3,4,5 and 6. In each case there is a factorization algebra of observables of the theory, which I will describe. The goal of these lectures will be to understand explicitly these factorization algebras and how they relate to quantum groups. As a first step, in this lecture, I will introduce the concept of line defect and state some theorems relating the category of line defects to the category of representations of certain quantum groups.