This book is specially written for those who are interested in the study of Laser Plasma Interaction. In current scenario our world is suffering from the energy crises and scientific community is looking towards Laser induced fusion as one of the possible solution for this. For the successful implementation of this Laser beam should propagate up to large Rayleigh length without beam distortion and without beam absorption. This book highlight the role of plasma channel in propagating the laser beam up to large Rayleigh lengths without being absorbed in the medium and without any distotion