INFORMATION RECORDING MEDIUM

摘要

PURPOSE:To eliminate the area/time overhead to be used in a recording mode of the sector data to be added and a reproduction mode of the added sector data, by adding a sector data identification flag and an additional data part to a sector format. CONSTITUTION:A sector data identification flag FLG is added to the sector identification parts ID1-IDn in sectors S1-Sn respectively to secure the control for reproduction of a data part only or reproduction of both the data part and an additional data part. At the same time, a data area 22 is divided into two parts for addition of an additional data part. In such constitution, the data can be added to the data in the same sector against an information recording medium having the parts ID1-IDn consisting of the sector address information and the flag FLG and two data parts (a data part A and an additional data part B) within a single sector.