The difference between JDK and JRE

Jre:java runtime Environment/java Run-time environment
Target User: Only the user who wants to run the Java program
The JRE contains: Deployment,user Interface toolkits,integration libraries,other base Libraries,lang and util base Libraries, Java V Irtual machine (Jvm,java VM).

Jdk:java Development Kit/java Development Kit
Target User: Java development programmer
The JDK is the developer kit that programmers need to write Java programs in the Java language. The JDK contains the JRE, as well as the compiler Javac, which compiles Java source code, and includes many tools for debugging and analyzing Java programs: Jconsole,java VISUALVM and other tools software, It also contains the documentation Javadoc and demo sample programs that are required for the Java program to be written.

JRE vs JDK vs JVM

Contact:
The JDK contains the JRE.
The JRE contains the JVM.

Difference:
If you need to run a Java program, just install the JRE.
If you need to write and run Java programs, you need to install the JDK.

The difference between JDK and JRE