Shingled Magnetic Recording has no positioning tracks. Due to the omission of positioning tracks, the tracks have a smaller distance to each other compared to other recording methods such as Perpendicular Magnetic Recording( PMR) and partially overlap. This means that more data can be written on the same magnetic surface, which is equivalent to an increase in storage density. To ensure that the read operation is error-free, the read area of the read/write head is narrower than that of the write area.
When updating data, the data to be changed and also the data of the neighboring tracks must be rewritten. To avoid having to rewrite the entire hard disk, the tracks are created in groupings so that only this area has to be rewritten. SMR technology has increased the storage capacity of hard disks to over 10 terabytes( TB).