Information when digitised is typically processed as data in computer systems using boolean logic and arithmatic. This more fundamentally means the information is represented by electrical signals (high (1) and low (0) voltage) that are routed through electronic circuits composed of logic gates. The logic gates themselves are made of transistors etched out of and doped in very pure silicium. All the logic and arithmatic the computer systems do can be achieved by combining logic gates in particular configurations.
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