Here's the short version. Malbolge is an esoteric programming language. Ben Olmstead published it in 1998. He named it for Malebolge, the eighth circle of Dante's Inferno — ditches of fraud. The design brief was almost honest cruelty: make a language that is nearly impossible to write.

Malbolge · Lesson 1
A language that was meant to be unwritable
Ben Olmstead, 1998, named for the eighth circle.
Lessons · Malbolge · Lesson 1 of 10 · On the house
A language that was meant to be unwritable
Ben Olmstead, 1998, named for the eighth circle.

The first Hello World took years. Andrew Cooke found one in 2000, two years after the spec. People later wrote tools that search for programs. We will not be those tools. We will look at the machine, match a fragment, and leave the rest as curiosity. Cipher would like this desk. Same beat: a puzzle, not a how-to for harm.
Hello, somehow
(=<`#9]~6ZY32Vx/4Rs+0No-&Jk*"Fh}lICl?p@4SPP^(>so+*7Quiz
Who published Malbolge, and when?
Check
Type the opening four characters of the still: (=<`
If a language is this hard on purpose, the lesson is the purpose. Next we look at the machine underneath.