#5 Piet

Developer: David Morgan-Mar

The code of this esoteric programming language resembles an abstract painting. ‘Piet’ was named after Piet Mondrian, the Dutch painter.

The language uses 20 separate colours, where each colour corresponds to a particular behavior. They are arranged in blocks. The compilation is guided by a "pointer" that moves around the image, from one continuous coloured region to the next. Procedures are carried through when the pointer exits a region.

#4 Brainf**k

Developer: Urban Muller

The esoteric language came out in 1993 was designed to challenge and amuse programmers. It stood out from other programming languages due to its extreme minimalism. He made it with intention of designing a language which could be implemented with the smallest possible compiler. However, the language is not suitable for practical use. The developer was also able to write a 200 byte compiler for the language. 

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