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

Question

Possible Duplicate:
Java SE 6 vs. JRE 1.6 vs. JDK 1.6 - What do these mean?

I need to install the latest version of J2SE. So right now I am at the specified link below trying to figure out how to proceed. The author of the book I got says to get the updated version of J2SE. I found JSE7u5 which I guess is the updated version. But on the right side of the page(which is still the specified link below) JDK and JRE show up. Am I supposed to install both of these to crete the full JSE package? Also I am running on a Mac.

http://www.oracle.com/technetwork/java/javase/downloads/index.html

Answer 1

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).

Answer 2

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.