Abstract: An apparatus for managing a printed document includes a storage medium capable of reversibly storing and erasing information, a printing/erasure device for executing printing to the storage medium and erasing a printed record, a document management server for managing information and security of the information, a write device for adding information onto the storage medium, and a monitor device for monitoring takeout of a printed document. A storage medium ID for identifying an individual medium is imparted to each medium. When printing, write, etc, are performed to the storage medium, the document management server manages the storage medium ID and a security level of a printed document file. The monitor device gives a warning not to take out the printed document in accordance with the security level of the document when the storage medium of printed documents is to be taken out.

Abstract: In an electronic pen system where it is required to identify each sheet of paper having an identical dot pattern, a document for inputting an identification code is prepared, where a code obtained by conversion according to a position of dot pattern is predetermined, and according to a combination of a plurality of codes determined based on the contents entered in the document, a type of the document is identified.