TPI
Updated: 11/13/2018 by Computer Hope
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Short for Tracks Per Inch, TPI is the number of tracks a disk can hold. For example, a 5.25-inch floppy disk (double density) has 48 TPI, a high-density 3.5-inch disk has 135 TPI, and hard drives have higher TPI, well into the thousands.
Computer acronyms, Floppy drive terms, Hard drive terms, TLA