Contrary to popular beliefs that compact cassettes are extinct as unnecessary, it is not so. Of course, they are not used as a music medium, but they can be used for long-term storage of information that does not need frequent and quick access.
Recently, Sony experts have developed a new material for magnetic tapes, which has an unprecedented recording density – 148 GB per square inch. So, one cassette can contain up to 185 TB, or approximately 3700 Blu-ray disks. However, the good old cassette is not likely to appear in everyday life and will be used only in the archives of the major data centers.