<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=windows-1252"> <title>Introduction to Disk Images</title> </head> <body style="background-color: rgb(255, 255, 255); font-family: verdana;" alink="#008000" link="#008000" vlink="#008000"> <h2 style="color: rgb(0, 128, 0);">Introduction to Disk Images</h2> <hr size="4"> <p>Everyone who once used an Apple II and now uses an IBM-compatible PC has the same problem: How can you make the PC read Apple floppy disks? Unfortunately, without special hardware, you can't. </p> <p>Floppy disks are analog devices, much like cassette tapes. For a computer to store digital data on a floppy disk, it must "encode" the data into an analog format. The Apple II used a method of encoding called Group Code Recording (GCR), while IBM-compatible PC's use the much more standard Modified Frequency Modulation (MFM) encoding. Since this is all done in hardware and cannot be bypassed, it is not possible for a PC program to "reprogram" the floppy drive in such a way that it could read Apple-formatted floppy diskettes. </p> <p>Therefore, instead of reading and writing disks directly, AppleWin uses disk images. A disk image is a single file, which you can store on your hard drive or on a PC floppy diskette, which contains all of the data from an entire Apple diskette. AppleWin treats an image exactly as if it were a real floppy disk. </p> </body> </html>