This book describes the interaction between the solar wind and the EArth's magnetic field( magnetosphere). Interplanetary Magnetic Field (IMF) impact on this interaction is essential. Different IMF orientation and their consequential influences on the said interaction were introduced in different chapters. The separation of these effects was meant to see what differences do that make on the driving parameters the solar wind-magnetosphere interaction. Our tool of the study was Particle-In-Cell (PIC), Electromagnetic and Relativistic code. This code was under development for more than three decades, originally written by Oscar Buneman, 1992 at Stanford University, CA, USA. The working version of the code we used, was developed within a framework of Franco-Polish protocol of cooperation. Nowadays, we have a better resolution in terms of grid size and number of particles per cells with real ion to electron mass ratios. The code lately was able to simulate very low energy and density of plasmasphere.