The default-jre is an excellent choice for most situations, thanks to the outstanding track of backwards compatibility of the Java Virtual Machine. Ubuntu offers the default-jre package, which is regularly updated to ship the latest version of the current OpenJDK JRE in Long Term Support (LTS). Moreover, the non LTS versions of Java are bringing a steady stream of innovation into the language, and also see some adoption.
Nowadays, Java 11 is the current Long Term Support (LTS) version, but Java 8 is still widely used. With new versions of Java released every 6 months, there are multiple versions available for use.
