The document discusses risk and return in investments. It defines key concepts like holding period return (HPR), expected return, standard deviation, variance, and coefficient of variation. It provides examples of calculating HPR for stocks based on purchase price, selling price, and dividends. Expected return is the average HPR and can be calculated in different ways. Risk is the variability in returns and can be measured using standard deviation, variance, beta, etc. The document also discusses portfolio returns and how to calculate expected portfolio return based on individual asset expected returns and weights.