Sub-Riemannian geometry and Lie groups. Part I
  These pages covers my expository talks during the seminar "Sub-Riemannian geometry and Lie groups" organised by the author and Tudor Ratiu at the Mathematics Department, EPFL, 2001. However, this is the first part of three, in preparation, dedicated to this subject. It covers, with mild modifications, an elementary introduction to the field. 
Marius Buliga