java -versioncommand from a shell prompt to see if java is installed. If you don't have version 1.8 or higher of the JDK installed on your system, use your package manager to install it or follow the directions at the OpenJDK install page.
PATHenvironment to add the
bin/directory of the installed JDK, but if the above command didn't work you will need to update the
PATHvariable manually, as described here.
scalaat the prompt:
scala>prompt indicates you are in the Scala REPL. For now, just type
:quitat the prompt to exit the REPL.