11 July, 2007

Random queries no. 119

One of a series of genuine search engine enquiries which successfully brought visitors to the Ministry.  Can I help?

why dont tapes and disks require presence of electricity to hold their memorised information?

Audio & video cassettes, 'floppy' diskettes and hard disks work by aligning the magnetism of particles embedded in a carrying medium (tape or disc/platter). Once that process has been completed, the physical state, and hence stored content, is retained until remagnetised.