Embodiments of the invention provide a disk drive that is capable of enhancing the storage capacity increase ratio while reducing the processing load for read/write operations. In one embodiment, a disk drive comprises a recording medium and a control section. The recording medium includes concentric or spiral data tracks. Each of the data tracks is provided with a plurality of circumferentially arranged sectors. The control section receives instructions for writing into a plurality of sectors, rearranges the data to be written into each sector into groups of N pieces of write data, and writes the data into N data tracks.