Initializing a Macintosh Disk



Disk initialization is the process of making a disk usable by the Macintosh Operating System. When shipped, most floppy disks are uninitialized because different operating systems have different initialization requirements. On the Macintosh computer, disk initialization consists of 3 steps: All three steps must be performed successfully before the disk is considered initialized (or valid).

The first step in the initialization process is disk formatting. Formatting a disk consists of writing special information onto a disk so that the disk driver can read from and write to the disk.

The second step in the disk-initialization process is disk verification. Verifying a disk consists of reading every bit on the disk to ensure that the disk has been formatted correctly and contains no bad blocks. If an error occurs during the reading of any single bit, the verification is considered unsuccessful.

The third and final step in the disk-initialization process is disk zeroing. Zeroing a disk consists of creating on the disk data structures and files necessary for the disk to be recognized as a hierarchical file system volume. In particular, zeroing a disk places a master directory block, a volume bitmap, and a catalog file in appropriate locations on the disk. The volume bitmap and catalog file are set up to represent a volume containing no user files. As a result, zeroing a disk makes any files previously located on the disk inaccessible.

At the present time, PC disks can be read be Macintoshes while Macintosh disks cannot be read by PC's. What this means is that you can use a disk which is PC formatted on both a Macintosh and a PC. On the other hand, if you have a Macintosh disk it can only be used by the Macintosh.

This part of the tutorial will teach you to initialize a Macintosh disk. Therefore, the disk that you create for this assignment may only be used on Macintosh computers without reformatting the disk for a PC computer. Again, if you decide to later format the disk for a PC computer the information on the disk will be completely erased.

Now that you know a little bit about the initialization process let's initialize your disk.

Put your 3 1/2 in floppy disk into your computer's disk drive.

Remember that the initialization process deletes everything that is on the disk so you probably want to be using a blank disk!

To initialize your disk:

Highlight your disk and then select Erase Disk... from the Special menu.

Something similar to the following should appear:



Under the Format sub-menu you have three choices. Since this assignment can only be done on a Macintosh computer we will be using the Macintosh 1.4 MB format.

Select Macintosh 1.4 MB from the Format drop-down list box and then click on Erase.

Your computer will then begin the erasing process which should take a few minutes. If you pay attention to the dialog box you will notice that the initialization does in fact consist of three processes.

You have successfully initialized your disk. Click on one of the following to continue the tutorial.

Next Topic: Opening An Application
Main Menu