title: What is Keystore?
body: <p>I have been getting:</p>
  
  <pre><code>sun.security.validator.ValidatorException: PKIX path building failed: 
  sun.security.provider.certpath.SunCertPathBuilderException: unable to find
  valid certification path to requested target
  .
  .
  Caused by: javax.net.ssl.SSLHandshakeException: sun.security.validator.
  ValidatorException: PKIX path building failed: sun.security.provider.
  certpath.SunCertPathBuilderException: unable to find valid certification 
  path to requested target
  </code></pre>
  
  <p>Searching on how to resolve this exception I have come across the term <code>Keystore</code> which I do not understand. What is Keystore in simple terms? How it is related to SSL?</p>