title: What are the key differences between OO in Smalltalk and Java?
body: <p>What are the key differences between OO in Smalltalk and Java? </p>
  
  <p>Please note that I am a Java programmer trying to expand his horizons by exploring Smalltalk. Currently I know almost nothing about Smalltalk except that it's purer than Java. Therefore I'll prefer the answer that shows how various Java concepts map to corresponding Smalltalk concepts and then introduces the Smalltalk concepts that don't exist in Java at all.</p>