The standard normal distribution -

Standard normal curve It is also known as bell curve or Gaussian distribution. The shape of the curve is like a bell → shaped curve. The data is distributed symmetrically on either side of a central value. Normal distribution curve looks symmetrical in the dispersion with the largest frequencies in the middle score and tapering down of frequencies towards the highest as well as the lowest score No tail. Normal distribution curve is based on mean and standard deviation. Mean, median and mode all coincide → No skew. Mean = median = mode = 0 Total area of curve is 1. Its standard deviation is 1. Variance is   Variance Variance is squared deviation from mean. For example, if deviation in a curve is 2 standard (2 SD) then variance will be square of this deviation i.e. (2 SD)2. So, Variance = SD2 In normal curve SD is 1. So variance = SD2 =12 =1