A mean, a median and a mode walk into a bar. The same data can give very different 'averages' depending on which one you pick — and a mischievous statistician can use that to mislead you.
Try it
Office salaries: $30k, $32k, $34k, $36k, $200k. What's the average?
Mean = $66.4k (skewed by the boss's salary). Median = $34k. Mode = no mode. The median is the most honest summary here.
When someone quotes 'the average', ask which one. If they're proud of a high number, they probably mean the mean. If they want to look modest, they'll quote the median.