Can anyone explain the meaning and usage of POJO or POCO
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  <p><strong>Possible Duplicate:</strong><br>
  <a href="http://stackoverflow.com/questions/3326319/what-does-the-term-plain-old-java-objectpojo-exactly-mean">What does the term Plain Old Java Object(POJO) exactly mean?</a>  </p>
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<p>I know those are recent concepts proposed by Mark Fowler. can anyone explain what the purpose of POJO or POCO and their usage?</p>
