Learning Programming with Eas — the Tutorial by Molaskes

How the Computer Works:03. Bit by Bit

The elementary unit of information is the bit, which means the distinction between exactly two states. Such two states can for instance be whether in a part of an electronic circuit energy is flowing (bit=1) or not (bit=0). Just like the power of moving electrons can be employed to move motors, feed lights, swing magnets and so on, it can also be used to control the flow of electricity itself. This is done with electronic switches which consist of a tiny strip of semiconductor materials. Their layers form a barrier, a strong resistor (bit=0), unless when fed from the side (input) by electrons, which then overloads the barrier to turn it into a conductor, to allow the main flow of electrons to be transmitted (bit=1) through this transistor. With transistors (electronic switches), one can build little electronic circuits that can turn bits on or off and allow them to be read. The computer's RAM (random access memory, "random" here means "read or write anytime") consists of zillions of these so-called flip-flop circuits, packed as microscopic structures into a microchip, much like biological tissue forms the organs of a living being. Other microphysics technologies allow bits to be stored when the electric current is turned off, such as hard disk drives, CD-RWs, DVDs, Flash — and ROM (read-only memory). ROM are bits "set in stone" to tell the computer upon being switched on what to do to start up.
03. Bit by Bit
T Two Things You Need
C Contact
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