Which part of diskette should never be touched?

The magnetic surface of a diskette, typically the side with the label or the shiny area, should never be touched. Touching this surface can transfer oils and dirt from your fingers, which can damage the data stored on the diskette. Additionally, any scratches or fingerprints can interfere with the disk drive's ability to read the data properly. Always handle diskettes by the edges to avoid contact with the magnetic surface.