esolang

An esolang, or esoteric programming language, is a programming language designed primarily to challenge, amuse, or explore ideas about programming rather than to be used for everyday software. Esos are typically not valued for practical productivity; their syntax, memory model, and semantics are intentionally unusual, obscure, or whimsical. Designers may emphasize minimalism, unusual data representations, artificial constraints, or visual and auditory expression. Many esolangs are Turing complete, although some are not, and a few exist mainly as puzzles or art.

Notable examples include Brainfuck (Urban Müller, 1993), which uses a minimal eight-command instruction set operating on an array of memory cells with a data pointer. Befunge (Chris Pressey, 1993) features a two-dimensional playfield where the instruction pointer can move in multiple directions. Piet (David Morgan-Mar, 1998) encodes programs as abstract images, with color transitions representing operations. Malbolge (Ben Olmstead, 1998) was designed to be nearly impossible to program by hand. Whitespace (Brady and Morris, 2003) uses only spaces, tabs, and linefeeds as code. Ook! and GolfScript are other examples frequently cited in code golf and esolang communities.

Interpreters and compilers for these languages exist in many ecosystems, and communities host challenges, tutorials, and collections of programs. Esolangs are studied to illustrate compiler design, parsing, and optimization under extreme constraints, and to explore the boundary between programming and art. They also serve as entertainment and as thought experiments about what constitutes a programming language.