When working between Macs and PCs, you have to keep a few things in mind.
Physically, Mac and PC floppy disks are the same 3 1/2 inch High Density (HD) disks, but must be formatted (or "initialized") for one kind of computer or the other. Power Macintoshes are capable of using PC-formatted disks, so you can get by quite nicely with a single disk.
For working in the labs in Carroll, you will need PC formatted disks. This will work well, as you will also need to get a PC-formatted disk to use in the Lexis/Nexis and U-Search terminals in Davis Library. Mac-formatted disks will not work in those computers.
It's a good idea to buy extra disks to make backup copies of your work every week or two, depending on your paranoia level. Speaking of paranoia, put your name and phone number on your disks, and mark whether they are formatted for Macs or PCs. Using different color labels or different color disks might help you avoid confusion.
Also, if your research subject will include a lot of visual information, such as a portfolio of photographs, or the history of an art museum collection, you may need additional disks.
Students using audio, video or large graphics files (especially for other visual communication courses) may use Zip disks in the lab PCs. Zip disks store more information than 70 conventional disks!