Music can be called the seed of evolution of portable storage. People wanted to store music which lead them to develop portable storage. In other words, man’s love for music made him invent it. Hence proved that music is by far the best thing that could happen to this world.
Gramophone (1900s – 1980s)
The first ever portable storage was on the gramophone. Thomas Edison is credited with creating the first device for recording and playing back sounds in 1877(Further developed by Emil Berliner in 1887). His approach used a very simple mechanism to store an analog wave mechanically.
In it, you had to speak into it, while the record rotated, as you spoke, the diaphragm vibrated vibrating the needle, and the needle scratched the signal onto the record. Similarly when the record was played, the needle vibrated due to the scratches, vibrating the diaphragm, converting the recorded vibrations into sound.
Tape recorder (1930s – 2000s)
Then came the tape recorder in 1930s. The tape recorder uses a tape of Iron Oxide (Fe2O3) which is a ferromagnetic material i.e. when the tape is exposed to magnetic flux, it gets permanently magnetised, and remembers it.
Inside the Tape recorder is a tiny electromagnet. When the audio signal is passed through it, it generates a magnetic flux. The magnetic flux is permanently remembered by the Iron Oxide tape. Then when we play the tape, the moving tape produces the same magnetic flux that it remembered, and the player produces the same audio signal through the speaker.
Floppy (1970s – 2000s) [1.44 MB]
Or many would call it: the “download” or “save” button everywhere, uses the same principle as of a tape recorder. It was developed in the seventies majorly by IBM, and was a main source of data exchange back then.
The Floppy works almost exactly like the tape recorder. However, it is shaped like a disk rather than a long thin ribbon. The disk has several Iron Oxide strips, which can be magnetised easily..The tracks are arranged in concentric rings so that the software can jump from “file 1” to “file 19” without having to fast forward through files 2-18. The diskette spins like a record and the heads move to the correct track.
CD – Compact Disk (1980s – 2000s) [737 MB]
The Compact Disk was developed by James Russel in the 1960s, and started selling commercially in the 80s.The working of a CD is somewhat inspired from a gramophone. Instead of the needle we have a laser, and instead of different vibrations, a CD player reads differences in the light reflected from the CD. But it’s not that simple.
A CD consists of an extremely thin, approximately 5 Km long spiral track on its surface, which goes outwards, like this:-
For writing data on a CD, a laser engraves pits on the CDs surface. When the CD is read, another low powered laser interprets those pits. A pit reflects light back to the reader; hence it returns the value 1. While if a bump reflects the laser’s light, the light moves away, which returns 0 to the CD reader.
Flash Drive (1990s – Now) [Upto 1 TB]
And then came this little man, who wiped out everything else because this guy stores data without any mechanical process, it’s all electronic, done using integrated circuits and logic gates only. Developed by Toshiba in the late 1980s, but at that time this was a very expensive technology. Over the years its extensive production and wide demand has made it this cheap. The way it works is pretty out of scope of this article, but I will surely give you a brief idea.
Inside the Flash Memory, there are 2 houses. One is the floating house, which can contain all the memory, and the other is the Control house, which controls the storage and deletion process. These houses are separated from each other with one high wall. When the user commands, the control house brings down the high wall and pushes electrons into the floating house, which store the data as the user has commanded. Nerds click here.
Originally Published at Economy Decoded.