What are the differences between private jre and public jre?

Question

What are the differences between private jre and public jre? Is there some official paper about this topic?

I didn\'t find any question on SO about this topic. Nor I was

Answer 1

The official answer, from Oracle:

Private Versus Public JRE

Installing the JDK also installs a private JRE and optionally a public copy. The private JRE is required to run the tools included with the JDK. It has no registry settings and is contained entirely in a jre directory (typically at C:\Program Files\jdk1.8.0\jre) whose location is known only to the JDK. On the other hand, the public JRE can be used by other Java applications, is contained outside the JDK (typically at C:\Program Files\Java\jre1.8.0), is registered with the Windows registry (at HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft), can be removed using Add/Remove Programs, might be registered with browsers, and might have the java.exe file copied to the Windows system directory (which would make it the default system Java platform).