title: abstraction vs abstract class
body: <p>according to  <a href="http://www.cs.cornell.edu/courses/cs211/2006sp/Lectures/L08-abstraction/08_abstraction.html">http://www.cs.cornell.edu/courses/cs211/2006sp/Lectures/L08-abstraction/08_abstraction.html</a></p>
  
  <p>abstraction comes in two flavors. One is function abstraction and the other is data abstraction. But where do abstract classes fit in? As far as i see, abstract classes are a totally different concept and even though the name suggests that it has something to do with OOP principles.</p>
  
  <p>Could someone please shed some light on this ?</p>