Batting average is a statistic in cricket, baseball, and softball that measures the performance of cricket batsmen, and baseball hitters. The two statistics are related in that baseball averages are directly descended from the concept of cricket averages.
In cricket, a player's batting average is the total number of runs he has scored divided by the number of times he has been out. Since the number of runs a player scores and how often he gets out are primarily measures of his own playing ability, and largely independent of his team mates, batting average is a good metric for an individual player's skill as a batsman. The number is also simple to interpret intuitively, being approximately the average number of runs the batsman scores per innings. Batting average has been used to gauge cricket players' relative skills since the 18th century.
Most players have career batting averages in the range of 20 to 40. This is also the desirable range for wicket-keepers, though some fall short and make up for it with keeping skill. Until a substantial increase in scores in the 21st century due to improved bats and smaller grounds among other factors, players who sustained an average above 50 through a career were considered exceptional, and before the development of the heavy roller in the 1870s an average of 25 was considered very good.