The document discusses key aspects of the normal distribution. It explains that a normal distribution is symmetrical and that percentages of observations can be determined within standard deviations of the mean. It also outlines the 68-95-99.7% rule where 68% of values lie within 1 standard deviation of the mean, 95% within 2 standard deviations, and 99.7% within 3 standard deviations. The document provides details on how to calculate standard scores or z-scores.