If you aren't planning to use Eclipse for Java development and want to save some disk space, install a JRE.
If you intend to use Eclipse for Java development, then you should install a JDK. You may either install a Java Runtime Environment (JRE), or a Java Development Kit (JDK), depending on what you want to do with Eclipse. Regardless of your operating system, you will need to install some Java virtual machine (JVM). In all cases, Eclipse requires a 64-bit JVMĪ Java Development Kit (JDK) includes many useful extras for Java developers including the source code for the standard Java libraries. If you are using Eclipse to do Java development, or are on macOS, install a JDK. Current releases of Eclipse require Java 11 JRE/JDK or newer.