This article is from the Apple II Csa2 FAQ, by Jeff Hurlburt with numerous contributions by others.
If you are at the usual System Desktop display and insert a new, "blank" Zip disk, you will be told that the disk's format is not recognized and asked if you want to have it formatted. Assuming you want ProDOS volumes or multiple HFS volumes, you should answer "NO": A new Zip disk is already formatted; what you need is to have it partitioned- - good, because partitioning takes about 30 seconds whereas a format takes 9-10 minutes. ProDOS is limited to 32,768kB ("32MB") per partition. The Finder does not know how to correctly format and partition a 100MB ProDOS disk. Reminder: If you want a disk to be able to boot ProDOS or any version of GS/OS (as in System 6.0.1), at least the first partition must be formatted for ProDOS. ---------------------------- By: Supertimer I say "Yes", if you want one big HFS-formatted Zip disk. (Unlike ProDOS, HFS allows volumes larger than 32MB.) Letting the Finder format the Zip disk for HFS gives you a 96MB (partition-table-less) "diskette" that's faster than one that has been partitioned, even if the partition = the whole disk. The "partitionless" HFS volume generated by formatting PC Zip disks from the Finder behaves just like a floppy and ejects and mounts like one (but with a hard disk icon). By: Rubywand