It is capable of creating and compiling programs.
It has everything the JRE has, but also the compiler (javac) and tools (like javadoc and jdb).
The JDK is the Java Development Kit, the full-featured SDK for Java. However, it cannot be used to create new programs. It is a package of everything necessary to run a compiled Java program, including the Java Virtual Machine (JVM), the Java Class Library, the java command, and other infrastructure. The JRE is the Java Runtime Environment, it covers most users needs. Installing this update will ensure that your Java applications continue to run as safely and efficiently as always. Only if you are planning to do some Java programming, you need to install the JDK. If you want to run Java programs on your computer, you only need to install the Java JRE.
