In the early 1980's, Micro computers used 8 inch, 5 1/4 inch and 3 1/2 inch “floppy disks” for storing data files .

The 8" floppy disks came into use for Micro computers in the mid 70's and were the predecessors to the hard drive that came into use around 1982.

FYI - Not mentioned in the video is the disk capacity.
8" floppy 80 KB to 1,212 KB
5 1/4" floppy 160 KB (in 1981) to 1.200 MB (in 1984)
3 1/2" floppy 720 KB to 1.44 MB

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