INFORMATION STORING DEVICE

PURPOSE:To obtain an information storing device which can utilize the capacity of an information storing medium to the maximum by closely arranging vacant areas produced when data are deleted on the medium. CONSTITUTION:A rewritable optical disk 20 is divided into areas (a), (b),... at every prescribed storing unit and data are stored in each divided area (a),... in groups. When the garbage of the disk 20 is selected on a keyboard 23, a CPU 34 sets a partition (a) as a work area and closely stores data stored in another area in the partition (a). When the partition (a) becomes full of data, the CPU 34 sets the next partition as a work area and stores data in the partition. After storing the data in the partitions, the CPU 34 updates the storing address of the retrieval code of each picture data stored on a magnetic disk 26. Thus the capacity of an optical disk device 22 is utilized to the maximum by continuously writing picture data of each group.