Abstract: Given a homeomorphism of a compact metric space and a continuous function, I will discuss the question of how big the set of Birkhoff generic points associated with the function is. This set plays an important role in studying dynamics of the map. To answer this question I will consider various ways of “measuring” a set: by using invariant measures, computing its Hausdorff dimension, and determining its Baire category. In the talk I will concentrate on the last characteristic — the Baire category — which gives some information on the topology of the set. This will be an introductory talk to the subject and it will be self-contained.