-associate key to record with hash function -applies to more than one attribute -good for looking up values based on equality -cannot answer range based queries
-associate key to record with hash function -applies to more than one attribute -good for looking up values based on equality -cannot answer range based queries
-used for easy/fast storing and accessing data -best for sets and maps -constant time (insert, delete, search) -num of items in h.t &lt; size of array &lt;&lt; keys