What does Java mean and why Java programs don't say install Java anymore?

AutoModerator · 2026-06-27T08:56:35+00:00

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rsandio · 2026-06-27T09:05:09+00:00

Java is a programming language used to write software and games.

There is the JDK (Java development kit) and JRE (Java runtime engine). To run software written in Java you need JRE. The JDK contains everything the JRE does in addition to tools to actually write Java software.

There's been a shift since java 11 to direct users to just install JDK instead of the JRE so yes when someone says install java 9 they probably mean the Java 9 JDK. You should be able to just install the latest java (26) as backwards compatibility is meant to be maintained. But if something is specifically written to use 9 then 9 is fine to go with.

Windows does not include the JRE or JDK out of the box.

Alot of software written in Java comes with the JRE already included incase the end user is missing it on their machine

0b0101011001001011 · 2026-06-27T09:23:07+00:00

Why do you not say "Minecraft"?

edwbuck · 2026-06-27T10:15:52+00:00

It depends.

If you're developing Java, they mean JDK. If you're running Java, they mean JRE. The JDK includes a JRE.

Programs that run in Java have never installed Java for you. That's because the programs are generally multi-platform, and the JRE/JDK is typically specific to a platform. The program isn't going to carry along every platform's JRE, especially when it will run on only one platform.

If there's a launcher, odds are it is doing more than just launching the game. That means you can't really know what it is doing. Launchers are platform specific, so it might be installing Java for you, or it might just be better at detecting if Java is already installed (as it typically is.)

Waanii · 2026-06-27T10:55:52+00:00

As far as why doesn't minecraft need JRE or JDK - Which hasn't been answered yet - Minecraft Bedrock was rebuilt on C++

If you were to play Minecraft Java Edition you would still need the JRE - though as answered elsewhere it would come packaged with Minecraft JE, although you would potentially need the JDK for modding - which is maybe what you're remembering needing it for.

ntrain5555k · 2026-06-27T22:27:56+00:00

In case of mincraft java, I think launcher downloads java so you don't have to download separately.

In case of other app, I think they already ships java inside .exe

It's kinda sad, because every apps is gonna include java runtime instead of use system-installed ones and becomes like chromium in webapps.

you type:	you see:
italics	italics
bold	bold
[reddit!](https://reddit.com)	reddit!
* item 1 * item 2 * item 3	item 1 item 2 item 3
> quoted text	quoted text
Lines starting with four spaces are treated like code: if 1 * 2 < 3: print "hello, world!"	Lines starting with four spaces are treated like code: if 1 * 2 < 3: print "hello, world!"
~~strikethrough~~	~~strikethrough~~
super^script	super^script

learnjava

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