An information storage medium is designed to assure stable continuous recording without adverse effect, even when many defective areas are present on the information storage medium. To record information onto the information storage medium, a file unit is defined as a first unit. A contiguous data area unit to be treated as a continuous recording area is defined as a second unit. Furthermore, recording is done in the contiguous data area units and a collection of the contiguous data area units is organized into the file unit. In addition, an information recording place is provided in such a manner that the contiguous data area unit is so set that it extends over the recording area of another file already recorded on the information storage medium and a defective area on the information storage medium.