A more thorough explanation:

Definition: The median is the middle value in a set of numbers. It is the value that separates the higher half from the lower half of the data set. It is different from the mean, which is the average of all the values in the set.

Examples:

• In the set of numbers {1, 3, 5, 7, 9}, the median is 5. It is the middle value when the numbers are arranged in order.
• If we have a class of 20 students and we arrange their test scores from lowest to highest, the median score is the score of the 10th student. Half of the class scored higher than that score and half scored lower.

The examples illustrate how the median is the value that divides the data set into two equal parts. It is useful in statistics to give a better understanding of the central tendency of the data.