Single period market models are the most elementary market models. Only a single period is considered. The beginning of the period is usu- ally denoted by the time t = 0 and the end of the period by time t = 1. At time t = 0 stock prices, bond prices,possibly prices of other financial assets or specific financial values are recorded and the financial agent can choose his investment, often a portfolio of stocks and bond. At time t = 1 prices are recorded again and the financial agent obtains a payoff corresponding to the value of his portfolio at time t = 1. Single period models are unrealistic in a way, that in reality trading takes place over many periods, but they allow us to illustrate and understand many of the important economic and mathematical principles in Financial Mathematics without being mathematically to complex and challeng- ing. We will later see, that more realistic multi period models can in- deed be obtained by the concatenation of many single period models. Single period models are therefore the building blocks of more compli- cated models.