Literate programming is a programming paradigm introduced by Donald Knuth in which a computer program is given an explanation of its logic in a natural language, such as English, interspersed with snippets of macros and traditional source code.
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Literate programming (LP) tools are used to obtain two representations from a literate source file: one suitable for further compilation or execution by a computer, the "tangled" code, and another for viewing as formatted documentation, which is said to be "woven" from the literate source. — Wikipedia↗
In .lit the main interface for both reading the woven result and editing the literate source are the same User Interface.