Which one to download: JDK or JRE? [duplicate]

Answer 1

Download the JDK if you want to do Java development. The JDK comes with the Java compiler (javac) which you will need for development. The JRE is the run time environment only - get this if you only want to run Java programs. If you get the JDK it comes with a JRE included so you don't need to get the JRE separately.

Answer 2

The Java Development Kit (JDK) is all you need.

The JRE is all you need if you just want to run Java programs.

The Java Platform hasn't been called J2SE for years. The last J2SE 5.0 was release in 2004 and has been End Of Life for a few years. http://en.wikipedia.org/wiki/Java_version_history

Answer 3

Just in case the other answers were not clear:

1. You need the JRE to run java apps; JRE is an initialism of Java Runtime Environment.
2. You need the JDK to develop java apps; JDK is an initialism of Java Development Kit. The JDK includes a JRE.
3. The current terms for the standard and enterprise editions are Java SE (standard) and Java EE (enterprise).