An optical recording medium having a read-only storage area and a writable
storage area and a recording/reproducing apparatus and method therefor.
The optical recording medium is a hybrid disc having both the read-only
storage area, which is suitable for mass production of information having
the same contents, and the writable storage area on which data can be
recorded, updated or added at a user's option. The read-only storage area
has a structure that is completely compatible with a digital versatile
disc read only memory (DVD-ROM) specification, and the writable storage
area is compatible with the recording/reproducing characteristics of a
writable DVD specification so that an existing reproducing-only apparatus
can read information from the read-only storage area, and data can be
recorded in the writable storage area using an apparatus obtained by
minimally changing an existing recording/reproducing apparatus while
maintaining the physical recording characteristics of the existing
recording/reproducing apparatus.