title: calculate distance
body: <p>i am designing a recruitment database, and i need it to perform several tasks that all involve integrating a way of calculating distance:</p>
  
  <p>1) calculate the distance the candidate lives from the client?</p>
  
  <p>2) calculate the clients within a radius of the candidates available for work on any given day?</p>
  
  <p>3) calculating the number of candidates with the correct qualifications for the vacancy within a radius of the client.</p>
  
  <p>as you can see i need to calculate the distance in 2 main ways 1) radius 2) as the crow flies, i would prefer exact distance but the first will do.
  i know that i can integrate Google maps or some other web based mapping but i want the system to be stand alone so it can function without an internet connection.
  the system will have a HTML5 front end and the Back end is in Mysql and PHP.</p>
  
  <p>thank you biagio </p>