Excel file and program structure

Question

I need to know for a school project how Excel work. Precisely I need to know what kind of structure is behind an Excel file and how the Excel program work with this file.

I know Excel is a Microsoft propriety and it' s not Open Source so I know I can' t find too much on this argument... But everything that can help me to understand how excel work it' s useful.

If I could not find something about Excel I will try to take a look at Open Office or Open Document format. So even some information about this will be real useful.

Thanks to all

Embarrassment

StackOverflow is generally for programming questions, your question would be much better suited on a site like SuperUser which is a similar Q&A site for power users of computer systems. – Rebate

Answer 1

You can find details of the MS Office BIFF file formats here in the microsoft.com library, while the Office Open XML format is published here on the ECMA site and here in the microsoft.com library.

You can find specifications for the OpenDocument format used by Open Office on the OASIS site

Contend

Answer 2

It is simpler than you may think.

An excel file is just a zip file of multiple XML documents. Each XML document corresponds to one spreadsheet in the Excel file.

You will find the XML sheets at xl\worksheets inside the zip folder.

You can scripting reading and writing to it.

Illegible

Change the extension to .zip and use winzip to open the folder containing the XML documents. – Illegible

This is only the case for Office Open XML (.xlsx) files, the older .xls files (up to Excel 2003) are a Bimnary Interface File Format (BIFF) proprietary format, although the format documentation is public – Contend

There's a lot more to the xlsx format than one xml file per worksheet as well... consider the shared strings table, and styles/themes – Contend