The Interchange File Format is a simple structured binary file format consisting of sized and typed chunks of data, selectively readable without having to know the format of each chunk. This functionality is similar to what XML provides for text documents, and the IFF format can indeed be viewed as a sort of a binary XML. IFF's extensibility is an excellent way of not breaking old applications when the file format changes, making it an excellent choice for your next application's data files. The IFF is also the simplest and the smallest such data format, ensuring that your files consist of real data rather than overhead and that your code spends more time on real work than on parsing the data file. This library defines the IFF header structures and provides simple algorithms for directly writing many of your objects as chunks and containers.