precision
Percentage of correct results. For example, if 10 apples are found in the target of query, 5 of them are apples and the other 5 are pears and bananas, then the accuracy rate =5/10=50%
recall
The percentage of results that are correct. For example, the query target is apples, and there are 8 apples in fact, but only 5 apples are returned in the query result, then the recall rate =5/8=62.5%