The Power "Brick"
Used with laptops and other electronic equipment, the external power adapter converts AC to a single DC voltage, and the laptop's internal power supply converts the DC to several different DC voltages. Although the power adapter is never included in the advertised weight of a laptop, most everyone keeps it in their laptop cases when they travel any distance.
The "Wall Wart" Adapter
The little black power adapter with its own wall plug is found with most every small electronic product. Dubbed "wall warts," they overlap into adjacent sockets, and many power strips add extra space to accommodate them.
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