Finite particle methods are the most powerful methods for the numerical simulation of motion of continuous medium, gas and electrostatic plasma dynamics and dynamics of charged particles. These methods allow studying the detailed characteristics of continuous medium taking into account the distribution functions of the particles (spatial, velocity and energy distributions), real self and external fields, particle-particle interactions and many other effects. A Particle-in-Cell method is one of finite particle methods and it is the most effective for simulations in Physics of the Plasma and charged particles. In this work Particle-in-Cell (PIC) simulation was carried out using MATLAB. Plasma in one dimension in the electrostatic limit was considered.