Introduction to Java Introduction (2)

Briefly introduce some common knowledge of Java. Of course, these knowledge are the basics of entry, and at the same time, they need to be used all the time. Not much to say. Today I will briefly describe the concept and relationship between the environment and the virtual machine and toolkit.
Java Virtual Machine: It is a hypothetical computer that runs all Java programs, referred to as JVM. It is the operating environment of Java and one of the most attractive features of Java. This feature here refers to the ability to run across platforms, that is, using Java programs. It can be used in Windows, Linux and Mac systems, and its function is equivalent to a translation effect.
JRE: It is the runtime environment of the Java program, which contains the JVM and the core class libraries required by the runtime.
JDK: It is a toolkit for Java program development. It contains JRE and tools used by developers.
The effect between them is shown in the figure: I

believe everyone can understand by looking at this figure. When I understand it, I will have an understanding of Java in my later learning as my auxiliary learning technology to observe from another angle.