title: What is the difference between synchronized and non-synchronized collection classes in Java?
body: <p>I was reading about Java's collections and then I read this line:</p>
  
  <blockquote>
    <p>"None of the collection classes are synchronized, but as you will see
    later in this chapter, it is possible to obtain synchronized
    versions."</p>
  </blockquote>
  
  <p>Can anyone tell me what is the difference between synchronized and non-synchronized collections in Java?</p>