Esoteric Home Languages

[Beware... it's definitely a long'un!]

Here's an interesting concept, for programmers bored with the mundane logic and common sense of conventional languages like C++ and Java. I stumbled upon this wiki and entered the world of Esoteric Programming Languages!

Esoteric: ["Es@tErIk]
adj.
Intended for or understood by only a particular group

The esoteric languages are semi-jokes which make the source code appear obfuscated. They also pride themselves on having extremely long source, even for simple programs like Hello World. One of the earlier languages, the controversially named Brainf*** has source code using only characters such as '>', '+' and '['. The Hello World program for this language is as follows:

++++++++++
[
    >+++++++>++++++++++>+++>+<<<<-
]
>++.
>+.
+++++++.
.
+++.
>++.
<<+++++++++++++++.
>.
+++.
------.
--------.
>+.
>.

Which is pretty cool. See the Brainf*** wiki (and be careful, it uses the letters 'u', 'c' and 'k') for an explanation on how this code works.

While Brainf*** is very low level, there are some other, more creative languages. David Morgan-Mar A.K.A. "DangerMouse" has designed a number of hilarious and clever languages.
DM's Esoteric Programming Lanaugages
All of them are jokes (most of which actually can be useful languages), and they're all worth a look. Beyond this, some of them actually represent some new programming paradigms, which, while mostly impractical, are cleverly designed.
In particular, Chef and Haifu are some high-level languages with impressive source code. The former makes your code look like a recipe, while the latter makes it look like an asian-philosophy haiki poem.

BIT makes for some highly ridiculous-looking programs, Piet's source code is a bitmap, and LenPEG represents a compression algorithm millions of times greater than normal ones (on certain cases).

HQ9+ is a great idea. Since people will often note a language's ease-of-use by looking at the Hello World program, the designer of HQ9+, Cliff L. Biffle, created a language with the shortest possible Hello World program:

H

As the name states, the program has just four commands: H, Q, 9 and +. The "Q" command does something extremely difficult in most languages: prints out a "Quine" or a copy of the program's own source code. The "9" prints the words to the song "99 Bottles of Beer", and the "+" increments the accumulator. As you can see, the language makes certain tasks extraordiarily easy. All other tasks are impossible.

The other language I wanted to point out was Shakespeare. This one seems to be one of the most well-fleshed out. Their website is a little out of commission at the moment, but you can still download the interpreter and the documentation.
Shakespeare Programming Language (SPL)
This language's code appears as a Shakspearean play. It forms very realistic-looking code, as demonstrated by this Hello World:

    Act II: Behind Hamlet's back.

    Scene I: Romeo and Juliet's conversation.

[Enter Romeo and Juliet]

Romeo:
 Speak your mind. You are as worried as the sum of yourself and the difference between my small smooth hamster and my nose. Speak your mind!

Juliet:
 Speak YOUR mind! You are as bad as Hamlet! You are as small as the difference between the square of the difference between my little pony and your big hairy hound and the cube of your sorry little codpiece. Speak your mind!

[Exit Romeo]

Update: This is actually only part of the source! The full Hello World is about four times longer and can be found here. (In case anyone's wondering why I didn't see this link on the wiki earlier, it's because I just added it myself!)

So... Esoterics are all-in-all completely useless when compared to actual programming languages, but this in no way stops them from being fun and clever. Definitely worth a long look.

Note: For anyone interested in what a normal Hello World program is for comparison, this is the standard C Hello World:

#include <stdio.h>

int main(void)
{
    printf("Hello World!\n");
    return 0;
}

The Hello World program simply prints the text "Hello World!" to the screen. Read more examples here.

"Well, that was fun. Useless, but fun."
- Dalboz of Gurth, Zork Grand Inquisitor