maven error/compiling: invalid target release: 1.8 [duplicate]

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• Fatal error compiling: invalid target release: 1.8 -> [Help 1] 1 answer

 Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.1:compile (default-compile) on project gs-rest-service:fatal error compiling: invalid target release:1.8

I'm new to java-ee programming and I can't understand this error.I haven't used any IDEs and tried to compile it using CMD. The command I have used is "mvn spring-boot:run" Can someone please explain what is this error and how to fix it.