The 5 Most Unreadable Esoteric Programming Languages Revealed

Every programmer knows many programming languages, most of which are high‑level and human‑readable, but there also exist low‑level languages that are hard to read. Even more extreme are the so‑called esoteric languages (esolangs), designed to push the boundaries of language design by discarding usability in favor of novelty, and they are popular among hackers and hobbyists.

1. Malbolge

Malbolge is considered one of the hardest programming languages; the first Malbolge program took two years to write after the language was created in 1998 by Ben Olmsted. Its creator never wrote a program in it.

Below is a Hello World program written in Malbolge:

(=<`#9]~6ZY32Vx/4Rs+0No-&Jk)"Fh}|Bcy?`=*z]Kw%oG4UUS0/@-ejc(:’8dc

2. Cow

Cow was released in early 2013 and is based on the idea of a cow’s limited vocabulary. The language distinguishes case and ignores all other words and symbols between commands, using various forms of the word “moo” (e.g., moO, MoO, mOo, mOO, Moo) as instructions.

Below is a Hello World program written in Cow:

MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO MoO

3. Brainfuck

Brainfuck, introduced in 1993 by Urban Müller, is an esoteric language consisting of only eight commands (<, >, +, –, ., ,, [, ]). It operates on an instruction pointer that moves through the command sequence. The eight commands are: < > + – . , [ ].

Below is a Hello World program written in Brainfuck:

++++++++++[>+++++++>++++++++++>+++>+<<<<-]>++.>+.+++++++..+++.>++.<<+++++++++++++++.>.+++.——.——–.>+.>.

4. INTERCAL

INTERCAL is a compiled language created by Don Woods and James M. Lyon that satirizes many aspects of other programming languages.

Below is a Hello World program written in INTERCAL:

PLEASE DO ,1 <- #13
DO ,1 SUB #1 <- #238
DO ,1 SUB #2 <- #112
DO ,1 SUB #3 <- #112
DO ,1 SUB #4 <- #0
DO ,1 SUB #5 <- #64
DO ,1 SUB #6 <- #238
DO ,1 SUB #7 <- #26
DO ,1 SUB #8 <- #248
DO ,1 SUB #9 <- #168
DO ,1 SUB #10 <- #24
DO ,1 SUB #11 <- #16
DO ,1 SUB #12 <- #158
DO ,1 SUB #13 <- #52
PLEASE READ OUT ,1
PLEASE GIVE UP

5. Whitespace

Whitespace, invented by Edwin Brady and Chris Morris, uses only space, tab, and line‑feed characters as meaningful symbols; all other characters are ignored. It is a stack‑based language with a virtual machine that has both a heap and a stack. The language was released on April 1 2003 as an April Fool’s joke.

Below is a Hello World program written in Whitespace:

(code not provided in the source).

Source: 程序师