INTRODUCTION TO FLOPPY DISKS
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The floppy disk is a magnetic storage medium which was invented in the
late 1960s. It was the predominate portable data storage medium in the
80s and early 90s. There are many sizes and variations of the floppy
disk, but for personal computer use the most common were 5.25 inch and
3.5 inch in size.

Floppy disks consist of a flexible plastic disk encased in a
protective covering. The plastic disk is coated with a magnetic
material. To read or write from the disk, the disk drive's head moves
across the spinning disk. To write to the disk, a current is put
through the magnetic head, creating a magnetic field which aligns the
magnetic particles on the disk's surface. To read data from the disk,
a small current is produced in the head from the magnetic field of the
disk's material as it spins beneath the head. There are a number of
methods to encode data on a floppy disk, but the important thing to
know is that binary data is not stored directly. The polarity of the
magnetic field is not read directly as ones and zeroes. Instead,
changes in polarity indirectly encode the data and the signal read
from the disk is analog, not digital.

Since the low-level data format of a floppy disk is not a digital
encoding of ones and zeros, the typical floppy disk image used by
emulators, etc., is not a one-to-one copy of the data stored on a
disk. It is better to think of a disk image as a copy of the digital
output of a floppy disk controller. A disk image is the host system's
view of the floppy disk after interpretation by disk controller
hardware.

Floppy disk copy protection mechanisms exploit the floppy controller's
(in)ability to read/write non-standard disk formats. Because of this,
a disk image of a copy protected disk will not be detected as a valid
copy by an emulator. The only means of using copy protected software
from a standard disk image is by cracking the software itself and
removing the copy protection. This is not ideal because any time the
software is modified, one must consider the possibility that bugs were
introduced. Furthermore, how many of the thousands of cracked floppy
disks out there have been adequately tested? Also, there is the case
of clever software that doesn't reveal the presence of copy protection
with only a cursory inspection.

ENTER THE KRYOFLUX
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Luckily, there is a solution to this problem. The Kryoflux is a USB
floppy disk controller for use on modern systems. The Kryoflux is
capable of reading and saving the raw magnetic flux transitions
of floppy disks. The software which comes with the kryoflux is also
flexible enough to detect bad reads if the native format of the disk
is known. Using the Kryoflux, it is possible to create raw disk images
that can be used to reproduce the original disk exactly, even
including copy protection.

The Kryoflux allows us to preserve floppy disks with unparalleled
fidelity. It can even be used to read disks that other floppy
controllers have trouble reading. However, even the Kryoflux has its
limits. Qver decades, the magnetic material on floppy disks will
break down, eventually resulting in unreadable disks. Proper storage
of disks will slow this process, but it is inevitable. As of 2017,
many floppy disks are already unreadable. In a few years many will
become most. And in a few more most will become all. If action isn't
taken now, the data saved on many floppy disks will be lost forever.

The internet is full of simple disk images in .IMG, .DSK, or .ADF
format.