Hashing is a common method of accessing data records. Consider, for example, a list of names:
John Smith Sarah Jones Roger Adams
To create an index, called a hash table, for these records, you would apply a formula to each name to produce a unique numeric value. So you might get something like:
1345873 John smith 3097905 Sarah Jones 4060964 Roger Adams
Then to search for the record containing <B>Sarah Jones</B>, you just need to reapply the formula, which directly yields the index key to the record. This is much more efficient than searching through all the records till the matching record is found.