diskette vs floppy disk

diskette

noun
  • A small, flexible, magnetic disk for storage and retrieval of data. 

floppy disk

noun
  • A removable disk used for storing digital data, measuring between 2 and 8 inches diagonally and storing between 80 KB and 240 MB. 

How often have the words diskette and floppy disk occurred in a corpus of books? (source: Google Ngram Viewer )