US Patent 7685522 Self-describing forms

Methods and apparatus, including computer program products, implementing and using techniques for generating a form and extracting user data from a form, the form including one or more data fields. Zoning information and structural information about the data fields are defined and encoded according to a symbology defined by rules for encoding information in a medium in which the form will be presented. The encoded zoning and structural information is incorporated in a representation of the form to be presented in the medium. Data entered on the form by a user can be extracted based on the encoded zoning and structural information.