What is JRE (Java Runtime environment)

JRE (Java Runtime environment)
JRE provides environment for running/executing programs.
You need to have JRE in your system for >
  • running Java programs.
JRE contains-
  • JVM,
  • class libraries (rt.jar)  and
  • other supporting libraries (external jars, Ex - ojdbc.jar for JDBC) for executing java program.
In short  JRE = JVM + class libraries (rt.jar)  + other libraries (if any).
JRE diagram >

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