The notion of "entropy pairs" was introduced by Blanchard in the 1990s. 

Given a topological dynamical system (X,T), a pair of points in X, x!=y is called an entropy pair if, for every standard open cover {U,V} of X such that (x,y) in Int(U^c)*Int(V^c), the entropy of the cover is greater than zero.

We will introduce the notions of completely positive entropy (c.p.e.), uniformly positive entropy (u.p.e.), discuss their relations and examine some basic properties of the entropy pairs. 

After laying out the foundations, we could discuss a disjointness theorem involving topological entropy and will also present the constructions of examples of various systems which are u.p.e. and c.p.e. and more interestingly, systems which are c.p.e. but not u.p.e.