Median

The median is the value that stands exactly in the middle when all the data is sorted; half the values are below it and half above.

The median is the mean's robust rival: because it looks only at the middle rank, not the absolute value, outliers do not budge it. That property makes the median a truer measure than the mean for skewed web data — session duration, page count, time on page — because it shows the 'typical user' rather than a mean polluted by the tail. But the median alone is not enough either: it is one middle number and says nothing about spread, so it is usually read beside percentiles to see both the center and the range. The common mistake is always choosing the mean out of familiarity, when for most behavioral web metrics the median is the more correct choice.