Sliding a plastic tab would allow floppies to be marked 'read-only'. The term 'diskette' was used to associate these new floppies with. These new 3.5-inch floppies would carry 'HD' for high density 720KB, and double-sided versions could hold 1.44MB of data. The 3.5-inch floppies were introduced with a hard plastic shell, with the selling point that you can slap on a mailing label and postage and send it 'as is' without the need for a separate envelope. Covering up the notches would mark them as read-only. We would convert single-sided floppies into double-sided ones by cutting out a notch in the outer sleeve. Later versions of these 5.25-inch floppies would be able to hold as much as 1.2MB of data. The 5.25-inch floppies we used could hold 360KB, and were flexible like the 8-inch models. We wrote in the BASIC language, and our databases were simple Comma-Separated-Variable (CSV) flat files.

Whenever we developed a clever piece of code, a subroutine or procedure, we would save it on a floppy disk and re-use it for our next project. We wrote computer programs to run on UNIX and Personal Computers for small businesses here in Tucson. While still in high school, my friend Franz Kurath and I formed 'Pearson Kurath Systems', a software development firm. I've been using floppies for the past thirty years. The 8-inch floppy fit conveniently in a manila envelope, sendable by standard mail, and could hold nearly 80KB of data. Imagine a floppy disk the size of a piece of standard paper. These were flexible plastic circles with a magnetic coating, and placed inside a square paper sleeve. IBM had drives that could write information, and sent out 'read-only' drives to the customer locations to receive these updates. IBM needed a way to send out small updates and patches for microcode of devices out in client locations.

It will be one of the many inventions celebrated as part of IBM's Centennial (100-year) anniversary.

IBM invented the floppy disk back in 1971, and continued to make improvements and enhancements through the 1980s and 1990s. The weather has warmed up here in Tucson so I started my Spring Cleaning early this year and unearthed from my garage a full of floppy diskettes.

Ibm formatted 2shd 1.44mb floppy disk