OpenJDK vs Java HotspotVM : <p>Are OpenJDK VM and Oracle Hotspot VM still two different JVMs?</p>

<p>I can't seem to find any somewhat official documentation on anything about OpenJDK VM. Even in OpenJDK homepage there is an HotSpot Group which develops HotSpot VM.</p>

<blockquote>
  <p>The HotSpot group is comprised of developers involved in the design, implementation, and maintanence of the HotSpot virtual machine</p>
</blockquote>

<p>However if I check java -version on my Windows machine it prints out</p>

<blockquote>
  <p>Java HotSpot(TM) 64-Bit Server VM</p>
</blockquote>

<p>But on my Ubuntu VPS </p>

<blockquote>
  <p>OpenJDK 64-Bit Server VM</p>
</blockquote>

<p>If those are two different VMs what are the main differences between them? Do they have different runtime flag sets?</p>
