Volume Management mounts the /vol/dev/diskette0 and /vol/dev/dsk/c0t6 directories onto /floppy and /cdrom:
Because of these mount points, when you insert a diskette, you can access it under /floppy/diskette-name. Likewise, when you insert a CD, you can access it under /cdrom/cd-name.
However, these mount points depend on proper formatting. If a diskette is formatted, the mount succeeds, but if it is unformatted, the mount fails and the diskette is only available under /vol/dev/diskette0. You can format diskettes according to the instructions in "How to Format a UFS Diskette" or "How to Format a DOS Diskette".