Abstract: I will give a basic introduction to the representation theory of \(GL_n(\mathbb{Q}_p) \) and describe some phenomena that do not appear in the complex representation theory of finite groups. In particular, I will introduce the so-called Bernstein block decomposition. In the second half I will explain how one can use the theory of Bernstein-Zelevinsky derivatives and the notion of « highest derivative partition » to study Bernstein blocks. This is joint work with David Helm.