Wolfram Notebook File Format

Wolfram Notebook File Format

The entire notebook, is just a plain ASCII text file, of Wolfram Language expression.

A notebook file content looks like this.

Notebook[{Cell[args], Cell[args], args}]

The Notebook[args], and Cell[args] are both just Wolfram Language functions.

When you open a Wolfram Notebook, the Frontend render it in a particular way, very much like how browser renders HTML.

WolframLang is analogous to HTML CSS JavaScript in one, and notebook is like browser.