title: Explanation about hashing and its use for data compression
body: <p>I am facing an application that uses hashing, but I cannot still figure out how it works. Here is my problem, hashing is used to generate some index, and with those indexes I access to different tables, and after I add the value of every table that I get using the indexes and with that I get my final value. This is done to reduce the memory requirements. The input to the hashing function is doing the XOR between a random constant number and some parameters from the application.</p>
  
  <p>Is this a typical hashing application?. The thing that I do not understand is how using hashing can we reduce the memory requirements?. Can anyone clarify this?.</p>
  
  <p>Thank you </p>