In creating an interoperable implementation, it may be helpful to understand specific implementation choices made by other products implementing the same standard. For example, portions of the standard may provide only general guidance, leaving specific implementation choices up to the application implementer; in some circumstances, it may be helpful for other implementers to understand those choices. In addition, products often vary from or extend standards either because of application deviations or to allow for use scenarios not originally envisioned by the specifications. Documentation of those variations and/or extensions may also be helpful to other implementers.
The implementer notes contained in this document provide information about how Office implements ISO/IEC-29500 Office Open XML File Formats [ISO/IEC-29500:2012], including areas where additional detail may be of benefit to other implementers and areas where the product is known to vary from or extend the specification.