Data Analysis is being able to find the following measures of central tendency: mean, mode, median, and range.
Many call the mean, the average. But there is more than just one value used to persuade people to their side; these are the mode, median, and range.

mean: add all values is set and divide by the number of values
mode: the most common value in the set; sometimes there is no value or multiple different common values {Most Often Data Entered}
median: the number in the middle of the sort list of values; when there is an even number the median is the average of the two middle numbers
range: the difference of the largest and smallest values