Discrete Parameter Martingales.- Continuous Time Processes.- The Ito Integral.- Stochastic Integration.- Semimartingales.- Pathwise Formula for the Stochastic Integral.- Continuous Semimartingales.- Predictable Increasing Processes.- The Davis Inequality.- Integral Representation of Martingales.- Dominating Process of a Semimartingale.- SDE driven by r.c.l.l. Semimartingales.- Girsanov Theorem.