This is a rant and it is my opinion and does not reflect that of Microsoft or others - It is my Opinion! From 1992 to 1995 I had to write document converters - I had to pick apart binary file formats and translate them to another format. It was hard work and I JUST WISHED people would create a largely encompassing standard for documents that was documented so I did not have to do all the work myself. Role forward to today, Office is still the prominent document format (which is now documented on http://msdn.microsoft.com ), but there is a new kid in town that encompass everything that an Office document is and more. This is the Open XML document format. People have cried for years that they wanted the Office Document standard to become more than a defacto standard, they wanted it to become a format an open standard. It was always going to be large, but to cover all the features and functions available in Office, it would have to be. There is no point in the standard being something different to that used in Office...