We experience convexity all the times and in many ways. The most prosaic example is our upright position, which is secured as long as the vertical projection of our center of gravity lies inside the convex envelope of our feet. Also convexity has a great impact on our every day life through numerous applications in industry, business, medicine and art. So do the problems of optimum allocation of resources and equilibrium of non cooperative games. The theory of convex functions is a part of the general subject of convexity, since a convex function is one whose epigraph is a convex set. Nonetheless it is an important theory, which touches almost all branches of mathematics. Using logconvexity we have Cauchy Means and their monotonicity.