Disks… digitalized data
Don’t you think that stuff like a CD/DVD/Blu-Ray disk or a flashcard for your camera are great inventions? The very first computer barely fit in one building and now we can hold a large amount of data in the palm of our hand.
Fascinating is it not? Although have you every wondered how these devices work?
Probably not.. but I’m going to tell you anyway :D… A CD for example is read from the inside to the outside. Ofcourse this is done in a circular way, the trail that is followed is covered with small pits and mountains, so to speak. The difference is height on the surface of the disk represents the data.
The speed of which the disk is rotating is constant, being 1,2 meters per second. The “height” of the surface of the disk is read by a laser. Depending on the light of the reflexion of the laser, the device can determine what data is written on the disk.
Flash memory is a specific type of EEPROM (electrically erasable programmable read-only memory). This memory, just like your hard drive, is non-volatile. No current is needed on the devide to keep your data stored and safe. let me spare you the technical details on this thing because it is rather complex. Even to explain :P… The only thing you should know is that these things are great and are used mostly for mp3 players, digital cameras, etc…
If you have any more questions about this subject, let me know