Differences between the JRE under the JDK installation path and the JRE installed independently

JDK environment variable configuration http://blog.csdn.net/xiaozhuaizhuai/article/details/3260925

A JRE is already installed by default under a subdocument under the JDK installation directory. And it is almost exactly the same as the files contained in the standalone installation of JRE6.

The built-in JRE and the standalone JRE in the JDK are a little different:
A complete stand-alone version of the JRE is included in the JDK installation file and will be executed automatically during JDK installation.

The tools inside the JDK are also written in Java, and they also require a set of JRE when they run, such as the JRE under the C:/Program files/java/jdk1.5.x/directory. The JRE under the C:/Program files/java/directory is used to execute the Java program we write ourselves. Of course, either of the two sets of JRE can be used to execute our own Java program, but the tools inside the JDK can only be executed by the JRE under the C:/Program files/java/jdk1.5.x/directory.

One is the Java Development Kit (Java Develop kit), one is the Java Runtime Environment (Java Runtime Environment)

http://blog.csdn.net/yuyulover/article/details/4427527