# How SuperDoc works

> Follow a DOCX file from OOXML package to editable document state and back.



A DOCX file is a package of OOXML parts. Those parts hold document content, styles, relationships, media, headers, footers, and other document data.

SuperDoc opens that package directly. It does not turn the file into HTML before editing.

## Open [#open]

The engine parses the OOXML parts and owns the editable document state. Source details that are not currently being edited stay attached to the document rather than being flattened into a web format.

## Render [#render]

The document state is projected into layout data. The layout engine paginates that data. The browser painter then draws the resolved pages as DOM.

The DOM is an output of the rendering pipeline. It is not the document format.

## Edit [#edit]

Editor input and headless operations change the same document state. The Document API defines how callers query content, identify targets, apply mutations, and read receipts.

## Write [#write]

When the document is saved or exported, the engine writes the changes back into the OOXML package. It does not reconstruct a DOCX from an HTML copy.

This is the no-conversion boundary: OOXML comes in, OOXML remains the source of document meaning, and OOXML goes out. Layout and DOM exist to display the document. They do not replace it.

Next, [choose your path](/start/choose-your-path).