An introduction to the collisionless shock waves propagating through the interplanetary space is presented. Basic concepts related to the propagation of information in ordinary gases and plasmas are reviewed. The wave modes in plasma and their steepening to shock waves are discussed. The shocks found in interplanetary space - planetary bow shocks, transient shocks driven by interplanetary coronal mass ejections and recurrent shocks due to the interaction of high-speed and low-speed solar wind streams are also discussed. Shocks can also be classified according to their propagation direction - away or toward the sun (forward and reverse shocks) and according if they are fast or slow mode magnetosonic waves steepened (fast and slow shocks). Finally, an example of calculated parameters for a transient interplanetary shock observed in solar wind near earth and its magnetospheric effects is presented.
solar wind; space weather; magnetosphere; MHD waves
