The standard Kalman filter is a filter based on Bayesian filter (3), with two extra assumptions: 1) the process and measurement noises are white and Gaussian, and 2) the process and measurement models are linear. The document derives the prediction and update equations for the Kalman filter, which provide an optimal estimate of the state x given prior state estimates and current measurements. The prediction equations forecast the next state and its covariance. An update is then made using a proportional gain and current measurement to provide a corrected state estimate.