See also: Hardware | Electricity
All personal computers contain a power supply unit, which supplies electricity to the machines different components. In some jurisdictions it is illegal to open and tamper with the self-contained packs, without electrical trade certification.
In the past, the flawed design of the IBM-clone personal computer power suppy was considered dangerous. Today the standard has been raised to a safer level for all new desktop computers.
Power supply on smaller devices is almost always done with a rechargeable battery.
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