SSD, Flash drives, Hard drives, CD/DVD, Floppy disks, Tape drives. More or less our storage technology was developed that way as far as I can remember.
I was very happy to read an article in tomshardware.com about how "Hard Drives 101: Magnetic Storage". It discusses the basic technology behind this marvel.
"Most permanent or semipermanent computer data is stored magnetically, meaning a stream of binary computer data bits (0s and 1s) is stored by magnetizing tiny pieces of metal embedded on the surface of a disk or tape in a pattern that represents the data. Later, this magnetic pattern can be read and converted back into the same original stream of bits. This is the principle of magnetic storage and the subject of this chapter.
History of Magnetic Storage
Before magnetic storage, the primary computer storage medium was punch cards (paper cards with holes punched in them to indicate character or binary data), originally invented by Herman Hollerith for use in the 1890 Census."
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