Whitespace is an esoteric programming language with syntax where only whitespace characters (space, tab and linefeed) have meaning – contrasting typical languages that largely ignore whitespace characters. [1][2]
As a consequence of its syntax, Whitespace source code can be contained within the whitespace of code written in a language that ignores whitespace – making the text a polyglot.[2]
Whitespace is an imperative, stack-based language. The programmer can push arbitrary-width integer values onto a stack and access a heap to store data.
An interpreter, along with its Haskell source code, is provided by the Whitespace creators.