According to the FI standard, a data model is specified with the following components:

• Document information
• Document format/type declaration items
• Character-related information
• Notation-related information
• Namespace-related information
• Element-related information
• Attribute information items
• Processing instruction information
• Unexpanded entity reference information
• Comment information
• Unparsed entity information

FI may be viewed as an XML gzip, even in cases where FI optimizes document size and computer resource usage. Like gzip, no information is lost during XML/FI conversion.