Eu achei que estava lá para FAT, File Allocation Table. Mas se você olhar para a Wikipedia, o "f" significa "fixo" como em "discos fixos".
excerto - link
For computer file systems, fdisk (for "fixed disk") is a command-line utility that provides disk partitioning functions. In versions of the Windows NT operating system line from Windows 2000 onwards, fdisk is replaced by more advanced tool called diskpart. Similar utilities exist for Unix-like systems.
fdisk da janela?
Concedido o acima tem mais a ver com a variante do Windows / DOS, mas o termo "disco fixo" faz muito sentido, uma vez que os discos rígidos eram frequentemente denominados "fixos" nos velhos tempos.
definição de "disco fixo"
A definição de "disco fixo" também diz o mesmo.
excerto - link
Noun 1. fixed disk - a rigid magnetic disk mounted permanently in a drive unit
Outras fontes dizem a mesma coisa:
Origens originais de "disco fixo"
A página da Wikipedia sobre unidades de disco rígido também tinha essa pepita:
trecho
In 1961 IBM introduced the model 1311 disk drive, which was about the size of a washing machine and stored two million characters on a removable disk pack. Users could buy additional packs and interchange them as needed, much like reels of magnetic tape. Later models of removable pack drives, from IBM and others, became the norm in most computer installations and reached capacities of 300 megabytes by the early 1980s. Non-removable HDDs were called fixed disk drives.