No. A distribution may be non-skewed and bimodal or skewed and
bimodal. Bimodal means that the distribution has two modes, or two
local maxima on the curve. Visually, one can see two peaks on the
distribution curve. Mixture problems (combination of two random
variables with different modes) can produce bimodal curves. See:
http://en.wikipedia.org/wiki/Bimodal_distribution A distribution is
skewed when the mean and median are different values. A
distribution is negatively skewed when the mean is less than the
median and positively skewed if the mean is greater than the
median. See: http://en.wikipedia.org/wiki/Skewness