Java Runtime Environment (JRE)

What is JRE?

• JRE stands for Java Runtime Environment
• It is used to run Java programs
• JRE is required on a system to execute Java applications
• It is mainly for end users, not for developers

Why JRE is Needed

• To execute Java programs
• To provide a runtime environment for Java applications
• To ensure Java programs run on different operating systems
• Without JRE, Java programs cannot run

Real-Life Example

Java program → Movie
JRE → DVD player

• Just like a DVD player runs a movie, JRE runs Java programs

Simple Java Example

** Consider this one-line Java code:**

System.out.println("Hello, Java!");

• This line prints output on the screen
• JRE helps execute this instruction
• Without JRE, this output will not be displayed

Where JRE is Used

• Running Java desktop applications
• Executing Java-based games
• Using Java software without writing code
• On user systems where only execution is required

JDK vs JRE

• JDK → Used to develop Java programs
• JRE → Used to run Java programs

Conclusion

• JRE is essential for running Java applications
• Beginners should understand that JRE is required even for simple Java output
• It allows Java programs to work smoothly across platforms