The world of groups is vast and meant for wandering! During this week, I will give seven short talks describing seven groups, or class of groups, that I find fascinating. These seven talks will be independent and I will have no intention of being exhaustive (this would be silly since there are uncountably many groups, even finitely generated!). In each talk, I will introduce the hero, state one or two results, and formulate one or two conjectures.[-]

Etienne Ghys is a French mathematician. His research focuses mainly on geometry and dynamical systems, though his mathematical interests are broad. He also expresses much interest in the historical development of mathematical ideas, especially the contribution of Henri Poincaré.
He co-authored the computer graphics mathematical movie Dimensions: A walk through mathematics!
Alumnus of the École Normale Supérieure de Saint-Cloud, he is currently a CNRS "directeur de recherche" at the École Normale Supérieure in Lyon. He is also editor-in-chief of the Publications Mathématiques de l'IHÉS and a member of the French Academy of Sciences.[-]